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|
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<section id="ctags">
<span id="ctags-1"></span><h1>ctags<a class="headerlink" href="#ctags" title="Permalink to this headline">¶</a></h1>
<p>Generate tag files for source code</p>
<dl class="field-list simple">
<dt class="field-odd">Version</dt>
<dd class="field-odd"><p>5.9.0</p>
</dd>
<dt class="field-even">Manual group</dt>
<dd class="field-even"><p>Universal Ctags</p>
</dd>
<dt class="field-odd">Manual section</dt>
<dd class="field-odd"><p>1</p>
</dd>
</dl>
<section id="synopsis">
<h2>SYNOPSIS<a class="headerlink" href="#synopsis" title="Permalink to this headline">¶</a></h2>
<div class="line-block">
<div class="line"><strong>ctags</strong> [<options>] [<source_file(s)>]</div>
<div class="line"><strong>etags</strong> [<options>] [<source_file(s)>]</div>
</div>
</section>
<section id="description">
<h2>DESCRIPTION<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
<p>The <em>ctags</em> and <em>etags</em> (see <code class="docutils literal notranslate"><span class="pre">-e</span></code> option) programs
(hereinafter collectively referred to as ctags,
except where distinguished) generate an index (or “tag”) file for a
variety of <em>language objects</em> found in <em>source file(s)</em>. This tag file allows
these items to be quickly and easily located by a text editor or other
utilities (<em>client tools</em>). A <em>tag</em> signifies a language object for which an index entry is
available (or, alternatively, the index entry created for that object).</p>
<p>Alternatively, ctags can generate a cross reference
file which lists, in human readable form, information about the various
language objects found in a set of source files.</p>
<p>Tag index files are supported by numerous editors, which allow the user to
locate the object associated with a name appearing in a source file and
jump to the file and line which defines the name. See the manual of your
favorite editor about utilizing ctags command and
the tag index files in the editor.</p>
<p>ctags is capable of generating different <em>kinds</em> of tags
for each of many different <em>languages</em>. For a complete list of supported
languages, the names by which they are recognized, and the kinds of tags
which are generated for each, see the <code class="docutils literal notranslate"><span class="pre">--list-languages</span></code> and <code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code>
options.</p>
<p>This man page describes <em>Universal Ctags</em>, an implementation of ctags
derived from <em>Exuberant Ctags</em>. The major incompatible changes between
Universal Ctags and Exuberant Ctags are enumerated in
<a class="reference internal" href="ctags-incompatibilities.7.html#ctags-incompatibilities-7"><span class="std std-ref">ctags-incompatibilities(7)</span></a>.</p>
<p>One of the advantages of Exuberant Ctags is that it allows a user to
define a new parser from the command line. Extending this capability is one
of the major features of Universal Ctags. <a class="reference internal" href="ctags-optlib.7.html#ctags-optlib-7"><span class="std std-ref">ctags-optlib(7)</span></a>
describes how the capability is extended.</p>
<p>Newly introduced experimental features are not explained here. If you
are interested in such features and ctags internals,
visit <a class="reference external" href="https://docs.ctags.io/">https://docs.ctags.io/</a>.</p>
</section>
<section id="command-line-interface">
<h2>COMMAND LINE INTERFACE<a class="headerlink" href="#command-line-interface" title="Permalink to this headline">¶</a></h2>
<p>Despite the wealth of available options, defaults are set so that
ctags is most commonly executed without any options (e.g.
“<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">*</span></code>”, or “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">-R</span></code>”), which will
create a tag file in the current directory for all recognized source
files. The options described below are provided merely to allow custom
tailoring to meet special needs.</p>
<p>Note that spaces separating the single-letter options from their parameters
are optional.</p>
<p>Note also that the boolean parameters to the long form options (those
beginning with <code class="docutils literal notranslate"><span class="pre">--</span></code> and that take a <code class="docutils literal notranslate"><span class="pre">[=(yes|no)]</span></code> parameter) may be omitted,
in which case <code class="docutils literal notranslate"><span class="pre">=yes</span></code> is implied. (e.g. <code class="docutils literal notranslate"><span class="pre">--sort</span></code> is equivalent to <code class="docutils literal notranslate"><span class="pre">--sort=yes</span></code>).
Note further that <code class="docutils literal notranslate"><span class="pre">=1</span></code>, <code class="docutils literal notranslate"><span class="pre">=on</span></code>, and <code class="docutils literal notranslate"><span class="pre">=true</span></code> are considered synonyms for <code class="docutils literal notranslate"><span class="pre">=yes</span></code>,
and that <code class="docutils literal notranslate"><span class="pre">=0</span></code>, <code class="docutils literal notranslate"><span class="pre">=off</span></code>, and <code class="docutils literal notranslate"><span class="pre">=false</span></code> are considered synonyms for <code class="docutils literal notranslate"><span class="pre">=no</span></code>.</p>
<p>Some options are either ignored or useful only when used while running in
etags mode (see <code class="docutils literal notranslate"><span class="pre">-e</span></code> option). Such options will be noted.</p>
<p><em><options></em> must precede the <em><source_file(s)></em> following the standard POSIX
convention.</p>
<p>Options taking language names will accept those names in either upper or
lower case. See the <code class="docutils literal notranslate"><span class="pre">--list-languages</span></code> option for a complete list of the
built-in language names.</p>
<section id="letters-and-names">
<h3>Letters and names<a class="headerlink" href="#letters-and-names" title="Permalink to this headline">¶</a></h3>
<p>Some options take one-letter flags as parameters (e.g. <code class="docutils literal notranslate"><span class="pre">--kinds-<LANG></span></code> option).
Specifying just letters help a user create a complicated command line
quickly. However, a command line including sequences of one-letter flags
becomes difficult to understand.</p>
<p>Universal Ctags accepts long-name flags in
addition to such one-letter flags. The long-name and one-letter flags can be mixed in an
option parameter by surrounding each long-name by braces. Thus, for an
example, the following three notations for <code class="docutils literal notranslate"><span class="pre">--kinds-C</span></code> option have
the same meaning:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="o">--</span><span class="n">kinds</span><span class="o">-</span><span class="n">C</span><span class="o">=+</span><span class="n">pLl</span>
<span class="o">--</span><span class="n">kinds</span><span class="o">-</span><span class="n">C</span><span class="o">=+</span><span class="p">{</span><span class="n">prototype</span><span class="p">}{</span><span class="n">label</span><span class="p">}{</span><span class="n">local</span><span class="p">}</span>
<span class="o">--</span><span class="n">kinds</span><span class="o">-</span><span class="n">C</span><span class="o">=+</span><span class="p">{</span><span class="n">prototype</span><span class="p">}</span><span class="n">L</span><span class="p">{</span><span class="n">local</span><span class="p">}</span>
</pre></div>
</div>
<p>Note that braces may be meta characters in your shell. Put
single quotes in such case.</p>
<p><code class="docutils literal notranslate"><span class="pre">--list-...</span></code> options shows one-letter flags and associated long-name flags.</p>
</section>
<section id="list-options">
<h3>List options<a class="headerlink" href="#list-options" title="Permalink to this headline">¶</a></h3>
<p>Universal Ctags introduces many <code class="docutils literal notranslate"><span class="pre">--list-...</span></code> options that provide
the internal data of Universal Ctags (See “<a class="reference internal" href="#listing-options">Listing Options</a>”). Both users and client tools may
use the data. <code class="docutils literal notranslate"><span class="pre">--with-list-header</span></code> and <code class="docutils literal notranslate"><span class="pre">--machinable</span></code> options
adjust the output of the most of <code class="docutils literal notranslate"><span class="pre">--list-...</span></code> options.</p>
<p>The default setting (<code class="docutils literal notranslate"><span class="pre">--with-list-header=yes</span></code> and <code class="docutils literal notranslate"><span class="pre">--machinable=no</span></code>)
is for using interactively from a terminal. The header that explains
the meaning of columns is simply added to the output, and each column is
aligned in all lines. The header line starts with a hash (’<code class="docutils literal notranslate"><span class="pre">#</span></code>’) character.</p>
<p>For scripting in a client tool, <code class="docutils literal notranslate"><span class="pre">--with-list-header=no</span></code> and
<code class="docutils literal notranslate"><span class="pre">--machinable=yes</span></code> may be useful. The header is not added to the
output, and each column is separated by tab characters.</p>
<p>Note the order of columns will change in the future release.
However, labels in the header will not change. So by scanning
the header, a client tool can find the index for the target
column.</p>
</section>
</section>
<section id="options">
<h2>OPTIONS<a class="headerlink" href="#options" title="Permalink to this headline">¶</a></h2>
<p>ctags has more options than listed here.
Options starting with an underscore character, such as <code class="docutils literal notranslate"><span class="pre">--_echo=<msg></span></code>,
are not listed here. They are experimental or for debugging purpose.</p>
<p>Notation: <code class="docutils literal notranslate"><span class="pre"><foo></span></code> is for a variable string <code class="docutils literal notranslate"><span class="pre">foo</span></code>, <code class="docutils literal notranslate"><span class="pre">[</span> <span class="pre">...</span> <span class="pre">]</span></code> for optional,
<code class="docutils literal notranslate"><span class="pre">|</span></code> for selection, and <code class="docutils literal notranslate"><span class="pre">(</span> <span class="pre">...</span> <span class="pre">)</span></code> for grouping. For example
<code class="docutils literal notranslate"><span class="pre">--foo[=(yes|no)]''</span> <span class="pre">means</span> <span class="pre">``--foo</span></code>, <code class="docutils literal notranslate"><span class="pre">-foo=yes</span></code>, or <code class="docutils literal notranslate"><span class="pre">-foo=no</span></code>.</p>
<section id="input-output-file-options">
<span id="option-input-output-file"></span><h3>Input/Output File Options<a class="headerlink" href="#input-output-file-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--exclude=<pattern></span></code></dt><dd><p>Add <em><pattern></em> to a list of excluded files and directories. This option may
be specified as many times as desired. For each file name considered
by ctags, each pattern specified using this option
will be compared against both the complete path (e.g.
<code class="docutils literal notranslate"><span class="pre">some/path/base.ext</span></code>) and the base name (e.g. <code class="docutils literal notranslate"><span class="pre">base.ext</span></code>) of the file, thus
allowing patterns which match a given file name irrespective of its
path, or match only a specific path.</p>
<p>If appropriate support is available
from the runtime library of your C compiler, then pattern may
contain the usual shell wildcards (not regular expressions) common on
Unix (be sure to quote the option parameter to protect the wildcards from
being expanded by the shell before being passed to ctags;
also be aware that wildcards can match the slash character, ‘<code class="docutils literal notranslate"><span class="pre">/</span></code>’).
You can determine if shell wildcards are available on your platform by
examining the output of the <code class="docutils literal notranslate"><span class="pre">--list-features</span></code> option, which will include
<code class="docutils literal notranslate"><span class="pre">wildcards</span></code> in the compiled feature list; otherwise, pattern is matched
against file names using a simple textual comparison.</p>
<p>If <em><pattern></em> begins with the character ‘<code class="docutils literal notranslate"><span class="pre">@</span></code>’, then the rest of the string
is interpreted as a file name from which to read exclusion patterns,
one per line. If pattern is empty, the list of excluded patterns is
cleared.</p>
<p>Note that at program startup, the default exclude list contains names of
common hidden and system files, patterns for binary files, and directories
for which it is generally not desirable to descend while processing the
<code class="docutils literal notranslate"><span class="pre">--recurse</span></code> option. To see the list of built-in exclude patterns, use
<code class="docutils literal notranslate"><span class="pre">--list-excludes</span></code>.</p>
<p>See also the description for <code class="docutils literal notranslate"><span class="pre">--exclude-exception=</span></code> option.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--exclude-exception=<pattern></span></code></dt><dd><p>Add <em><pattern></em> to a list of included files and directories. The pattern
affects the files and directories that are excluded by the pattern
specified with <code class="docutils literal notranslate"><span class="pre">--exclude=</span></code> option.</p>
<p>For an example, you want ctags to ignore all files
under <code class="docutils literal notranslate"><span class="pre">foo</span></code> directory except <code class="docutils literal notranslate"><span class="pre">foo/main.c</span></code>, use the following command
line: <code class="docutils literal notranslate"><span class="pre">--exclude=foo/*</span> <span class="pre">--exclude-exception=foo/main.c</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--filter[=(yes|no)]</span></code></dt><dd><p>Makes ctags behave as a filter, reading source
file names from standard input and printing their tags to standard
output on a file-by-file basis. If <code class="docutils literal notranslate"><span class="pre">--sort</span></code> is enabled, tags are sorted
only within the source file in which they are defined. File names are
read from standard input in line-oriented input mode (see note for <code class="docutils literal notranslate"><span class="pre">-L</span></code>
option) and only after file names listed on the command line or from
any file supplied using the <code class="docutils literal notranslate"><span class="pre">-L</span></code> option. When this option is enabled,
the options <code class="docutils literal notranslate"><span class="pre">-f</span></code>, <code class="docutils literal notranslate"><span class="pre">-o</span></code>, and <code class="docutils literal notranslate"><span class="pre">--totals</span></code> are ignored. This option is quite
esoteric and is disabled by default.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--filter-terminator=<string></span></code></dt><dd><p>Specifies a <em><string></em> to print to standard output following the tags for
each file name parsed when the <code class="docutils literal notranslate"><span class="pre">--filter</span></code> option is enabled. This may
permit an application reading the output of ctags
to determine when the output for each file is finished.</p>
<p>Note that if the
file name read is a directory and <code class="docutils literal notranslate"><span class="pre">--recurse</span></code> is enabled, this string will
be printed only once at the end of all tags found for by descending
the directory. This string will always be separated from the last tag
line for the file by its terminating newline.</p>
<p>This option is quite esoteric and is empty by default.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--links[=(yes|no)]</span></code></dt><dd><p>Indicates whether symbolic links (if supported) should be followed.
When disabled, symbolic links are ignored. This option is on by default.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--maxdepth=<N></span></code></dt><dd><p>Limits the depth of directory recursion enabled with the <code class="docutils literal notranslate"><span class="pre">--recurse</span></code>
(<code class="docutils literal notranslate"><span class="pre">-R</span></code>) option.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--recurse[=(yes|no)]</span></code></dt><dd><p>Recurse into directories encountered in the list of supplied files.</p>
<p>If the list of supplied files is empty and no file list is specified with
the <code class="docutils literal notranslate"><span class="pre">-L</span></code> option, then the current directory (i.e. ‘<code class="docutils literal notranslate"><span class="pre">.</span></code>’) is assumed.
Symbolic links are followed by default (See <code class="docutils literal notranslate"><span class="pre">--links</span></code> option). If you don’t like these behaviors, either
explicitly specify the files or pipe the output of <code class="docutils literal notranslate"><span class="pre">find(1)</span></code> into
“<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">-L</span> <span class="pre">-</span></code>” instead. See, also, the <code class="docutils literal notranslate"><span class="pre">--exclude</span></code> and
<code class="docutils literal notranslate"><span class="pre">--maxdepth</span></code> to limit recursion.</p>
<p>Note: This option is not supported on
all platforms at present. It is available if the output of the <code class="docutils literal notranslate"><span class="pre">--help</span></code>
option includes this option.</p>
</dd>
</dl>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">-R</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--recurse</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-L</span> <span class="pre"><file></span></code></dt><dd><p>Read from <em><file></em> a list of file names for which tags should be generated.</p>
<p>If file is specified as ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’, then file names are read from standard
input. File names read using this option are processed following file
names appearing on the command line. Options are also accepted in this
input. If this option is specified more than once, only the last will
apply.</p>
<p>Note: file is read in line-oriented mode, where a new line is
the only delimiter and non-trailing white space is considered significant,
in order that file names containing spaces may be supplied
(however, trailing white space is stripped from lines); this can affect
how options are parsed if included in the input.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--append[=(yes|no)]</span></code></dt><dd><p>Indicates whether tags generated from the specified files should be
appended to those already present in the tag file or should replace them.
This option is <code class="docutils literal notranslate"><span class="pre">no</span></code> by default.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-a</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--append</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-f</span> <span class="pre"><tagfile></span></code></dt><dd><p>Use the name specified by <em><tagfile></em> for the tag file (default is “<code class="docutils literal notranslate"><span class="pre">tags</span></code>”,
or “<code class="docutils literal notranslate"><span class="pre">TAGS</span></code>” when running in etags mode). If <em><tagfile></em> is specified as ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>‘,
then the tags are written to standard output instead.</p>
<p>ctags
will stubbornly refuse to take orders if tagfile exists and
its first line contains something other than a valid tags line. This
will save your neck if you mistakenly type “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">-f</span>
<span class="pre">*.c</span></code>”, which would otherwise overwrite your first C file with the tags
generated by the rest! It will also refuse to accept a multi-character
file name which begins with a ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ (dash) character, since this most
likely means that you left out the tag file name and this option tried to
grab the next option as the file name. If you really want to name your
output tag file <code class="docutils literal notranslate"><span class="pre">-ugly</span></code>, specify it as “<code class="docutils literal notranslate"><span class="pre">-f</span> <span class="pre">./-ugly</span></code>”.</p>
<p>This option must
appear before the first file name. If this option is specified more
than once, only the last will apply.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-o</span> <span class="pre"><tagfile></span></code></dt><dd><p>Equivalent to “<code class="docutils literal notranslate"><span class="pre">-f</span> <span class="pre">tagfile</span></code>”.</p>
</dd>
</dl>
</section>
<section id="output-format-options">
<span id="option-output-format"></span><h3>Output Format Options<a class="headerlink" href="#output-format-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--format=(1|2)</span></code></dt><dd><p>Change the format of the output tag file. Currently the only valid
values for level are 1 or 2. Level 1 specifies the original tag file
format and level 2 specifies a new extended format containing extension
fields (but in a manner which retains backward-compatibility with
original <code class="docutils literal notranslate"><span class="pre">vi(1)</span></code> implementations). The default level is 2.
[Ignored in etags mode]</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--output-format=(u-ctags|e-ctags|etags|xref|json)</span></code></dt><dd><p>Specify the output format. The default is <code class="docutils literal notranslate"><span class="pre">u-ctags</span></code>.
See <a class="reference internal" href="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a> for <code class="docutils literal notranslate"><span class="pre">u-ctags</span></code> and <code class="docutils literal notranslate"><span class="pre">e-ctags</span></code>.
See <code class="docutils literal notranslate"><span class="pre">-e</span></code> for <code class="docutils literal notranslate"><span class="pre">etags</span></code>, and <code class="docutils literal notranslate"><span class="pre">-x</span></code> for <code class="docutils literal notranslate"><span class="pre">xref</span></code>.
<code class="docutils literal notranslate"><span class="pre">json</span></code> format is available only if
the ctags executable is built with <code class="docutils literal notranslate"><span class="pre">libjansson</span></code>.
See <a class="reference internal" href="ctags-client-tools.7.html#ctags-client-tools-7"><span class="std std-ref">ctags-client-tools(7)</span></a> for more about <code class="docutils literal notranslate"><span class="pre">json</span></code> format.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-e</span></code></dt><dd><p>Same as <code class="docutils literal notranslate"><span class="pre">--output-format=etags</span></code>.
Enable etags mode, which will create a tag file for use with the Emacs
editor. Alternatively, if ctags is invoked by a
name containing the string “etags” (either by renaming,
or creating a link to, the executable), etags mode will be enabled.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-x</span></code></dt><dd><p>Same as <code class="docutils literal notranslate"><span class="pre">--output-format=xref</span></code>.
Print a tabular, human-readable cross reference (xref) file to standard
output instead of generating a tag file. The information contained in
the output includes: the tag name; the kind of tag; the line number,
file name, and source line (with extra white space condensed) of the
file which defines the tag. No tag file is written and all options
affecting tag file output will be ignored.</p>
<p>Example applications for this
feature are generating a listing of all functions located in a source
file (e.g. “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">-x</span> <span class="pre">--kinds-c=f</span> <span class="pre">file</span></code>”), or generating
a list of all externally visible global variables located in a source
file (e.g. “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">-x</span> <span class="pre">--kinds-c=v</span> <span class="pre">--extras=-F</span> <span class="pre">file</span></code>”).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--sort=(yes|no|foldcase)</span></code></dt><dd><p>Indicates whether the tag file should be sorted on the tag name
(default is <code class="docutils literal notranslate"><span class="pre">yes</span></code>). Note that the original <code class="docutils literal notranslate"><span class="pre">vi(1)</span></code> required sorted tags.
The <code class="docutils literal notranslate"><span class="pre">foldcase</span></code> value specifies case insensitive (or case-folded) sorting.
Fast binary searches of tag files sorted with case-folding will require
special support from tools using tag files, such as that found in the
ctags readtags library, or Vim version 6.2 or higher
(using “<code class="docutils literal notranslate"><span class="pre">set</span> <span class="pre">ignorecase</span></code>”).
[Ignored in etags mode]</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-u</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--sort=no</span></code> (i.e. “unsorted”).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--etags-include=<file></span></code></dt><dd><p>Include a reference to <em><file></em> in the tag file. This option may be specified
as many times as desired. This supports Emacs’ capability to use a
tag file which <em>includes</em> other tag files. [Available only in etags mode]</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--input-encoding=<encoding></span></code></dt><dd><p>Specifies the <em><encoding></em> of the input files.
If this option is specified, Universal Ctags converts the input from this
encoding to the encoding specified by <code class="docutils literal notranslate"><span class="pre">--output-encoding=encoding</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--input-encoding-<LANG>=<encoding></span></code></dt><dd><p>Specifies a specific input <em><encoding></em> for <em><LANG></em>. It overrides the global
default value given with <code class="docutils literal notranslate"><span class="pre">--input-encoding</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--output-encoding=<encoding></span></code></dt><dd><p>Specifies the <em><encoding></em> of the tags file.
Universal Ctags converts the encoding of input files from the encoding
specified by <code class="docutils literal notranslate"><span class="pre">--input-encoding=<encoding></span></code> to this encoding.</p>
<p>In addition <em><encoding></em> is specified at the top the tags file as the
value for the <code class="docutils literal notranslate"><span class="pre">TAG_FILE_ENCODING</span></code> pseudo-tag. The default value of
<em><encoding></em> is <code class="docutils literal notranslate"><span class="pre">UTF-8</span></code>.</p>
</dd>
</dl>
</section>
<section id="language-selection-and-mapping-options">
<span id="option-lang-mapping"></span><h3>Language Selection and Mapping Options<a class="headerlink" href="#language-selection-and-mapping-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--language-force=(<language>|auto)</span></code></dt><dd><p>By default, ctags automatically selects the language
of a source file, ignoring those files whose language cannot be
determined (see “<a class="reference internal" href="#determining-file-language">Determining file language</a>”). This option forces the specified
<em>language</em> (case-insensitive; either built-in or user-defined) to be used
for every supplied file instead of automatically selecting the language
based upon its extension.</p>
<p>In addition, the special value <code class="docutils literal notranslate"><span class="pre">auto</span></code> indicates
that the language should be automatically selected (which effectively
disables this option).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--languages=[+|-](<list>|all)</span></code></dt><dd><p>Specifies the languages for which tag generation is enabled, with <em><list></em>
containing a comma-separated list of language names (case-insensitive;
either built-in or user-defined).</p>
<p>If the first language of <em><list></em> is not
preceded by either a ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’, the current list (the current settings
of enabled/disabled languages managed in ctags internally)
will be cleared before adding or removing the languages in <em><list></em>. Until a ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ is
encountered, each language in the <em><list></em> will be added to the current list.</p>
<p>As either the ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ is encountered in the <em><list></em>, the languages
following it are added or removed from the current list, respectively.
Thus, it becomes simple to replace the current list with a new one, or
to add or remove languages from the current list.</p>
<p>The actual list of
files for which tags will be generated depends upon the language
extension mapping in effect (see the <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> option). Note that the most of
languages, including user-defined languages, are enabled unless explicitly
disabled using this option. Language names included in list may be any
built-in language or one previously defined with <code class="docutils literal notranslate"><span class="pre">--langdef</span></code>.</p>
<p>The default
is <code class="docutils literal notranslate"><span class="pre">all</span></code>, which is also accepted as a valid argument. See the
<code class="docutils literal notranslate"><span class="pre">--list-languages</span></code> option for a list of the all (built-in and user-defined)
language names.</p>
<p>Note <code class="docutils literal notranslate"><span class="pre">--languages=</span></code> option works cumulative way; the option can be
specified with different arguments multiple times in a command line.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--alias-<LANG>=[+|-](<pattern>|default)</span></code></dt><dd><p>Adds (’<code class="docutils literal notranslate"><span class="pre">+</span></code>’) or removes (’<code class="docutils literal notranslate"><span class="pre">-</span></code>’) an alias <em><pattern></em> to a language specified
with <em><LANG></em>. ctags refers to the alias pattern in
“<a class="reference internal" href="#determining-file-language">Determining file language</a>” stage.</p>
<p>The parameter <em><pattern></em> is not a list. Use this option multiple
times in a command line to add or remove multiple alias
patterns.</p>
<p>To restore the default language aliases, specify <code class="docutils literal notranslate"><span class="pre">default</span></code>.</p>
<p>Using <code class="docutils literal notranslate"><span class="pre">all</span></code> for <em><LANG></em> has meaning in following two cases:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">--alias-all=</span></code></dt><dd><p>This clears aliases setting of all languages.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--alias-all=default</span></code></dt><dd><p>This restores the default languages aliases for all languages.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--guess-language-eagerly</span></code></dt><dd><p>Looks into the file contents for heuristically guessing the proper language parser.
See “<a class="reference internal" href="#determining-file-language">Determining file language</a>”.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-G</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--guess-language-eagerly</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--langmap=<map>[,<map>[...]]</span></code></dt><dd><p>Controls how file names are mapped to languages (see the <code class="docutils literal notranslate"><span class="pre">--list-maps</span></code>
option). Each comma-separated <em><map></em> consists of the language name (either
a built-in or user-defined language), a colon, and a list of <em>file
extensions</em> and/or <em>file name patterns</em>. A file extension is specified by
preceding the extension with a period (e.g. <code class="docutils literal notranslate"><span class="pre">.c</span></code>). A file name pattern
is specified by enclosing the pattern in parentheses (e.g.
<code class="docutils literal notranslate"><span class="pre">([Mm]akefile)</span></code>).</p>
<p>If appropriate support is available from the runtime
library of your C compiler, then the file name pattern may contain the usual
shell wildcards common on Unix (be sure to quote the option parameter to
protect the wildcards from being expanded by the shell before being
passed to ctags). You can determine if shell wildcards
are available on your platform by examining the output of the
<code class="docutils literal notranslate"><span class="pre">--list-features</span></code> option, which will include <code class="docutils literal notranslate"><span class="pre">wildcards</span></code> in the compiled
feature list; otherwise, the file name patterns are matched against
file names using a simple textual comparison.</p>
<p>When mapping a file extension with <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> option,
it will first be unmapped from any other languages. (<code class="docutils literal notranslate"><span class="pre">--map-<LANG></span></code>
option provides more fine-grained control.)</p>
<p>If the first character in a <em><map></em> is a plus sign (’<code class="docutils literal notranslate"><span class="pre">+</span></code>’), then the extensions and
file name patterns in that map will be appended to the current map
for that language; otherwise, the map will replace the current map.
For example, to specify that only files with extensions of <code class="docutils literal notranslate"><span class="pre">.c</span></code> and <code class="docutils literal notranslate"><span class="pre">.x</span></code> are
to be treated as C language files, use <code class="docutils literal notranslate"><span class="pre">--langmap=c:.c.x</span></code>; to also add
files with extensions of <code class="docutils literal notranslate"><span class="pre">.j</span></code> as Java language files, specify
<code class="docutils literal notranslate"><span class="pre">--langmap=c:.c.x,java:+.j</span></code>. To map makefiles (e.g. files named either
<code class="docutils literal notranslate"><span class="pre">Makefile</span></code>, <code class="docutils literal notranslate"><span class="pre">makefile</span></code>, or having the extension <code class="docutils literal notranslate"><span class="pre">.mak</span></code>) to a language
called <code class="docutils literal notranslate"><span class="pre">make</span></code>, specify <code class="docutils literal notranslate"><span class="pre">--langmap=make:([Mm]akefile).mak</span></code>. To map files
having no extension, specify a period not followed by a non-period
character (e.g. ‘<code class="docutils literal notranslate"><span class="pre">.</span></code>’, <code class="docutils literal notranslate"><span class="pre">..x</span></code>, <code class="docutils literal notranslate"><span class="pre">.x.</span></code>).</p>
<p>To clear the mapping for a
particular language (thus inhibiting automatic generation of tags for
that language), specify an empty extension list (e.g. <code class="docutils literal notranslate"><span class="pre">--langmap=fortran:</span></code>).
To restore the default language mappings for a particular language,
supply the keyword <code class="docutils literal notranslate"><span class="pre">default</span></code> for the mapping. To specify restore the
default language mappings for all languages, specify <code class="docutils literal notranslate"><span class="pre">--langmap=default</span></code>.</p>
<p>Note that file name patterns are tested before file extensions when inferring
the language of a file. This order of Universal Ctags is different from
Exuberant Ctags. See <a class="reference internal" href="ctags-incompatibilities.7.html#ctags-incompatibilities-7"><span class="std std-ref">ctags-incompatibilities(7)</span></a> for the background of
this incompatible change.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--map-<LANG>=[+|-]<extension>|<pattern></span></code></dt><dd><p>This option provides the way to control mapping(s) of file names to
languages in a more fine-grained way than <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> option.</p>
<p>In ctags, more than one language can map to a
file name <em><pattern></em> or file <em><extension></em> (<em>N:1 map</em>). Alternatively,
<code class="docutils literal notranslate"><span class="pre">--langmap</span></code> option handle only <em>1:1 map</em>, only one language
mapping to one file name <em><pattern></em> or file <em><extension></em>. A typical N:1
map is seen in C++ and ObjectiveC language; both languages have
a map to <code class="docutils literal notranslate"><span class="pre">.h</span></code> as a file extension.</p>
<p>A file extension is specified by preceding the extension with a period (e.g. <code class="docutils literal notranslate"><span class="pre">.c</span></code>).
A file name pattern is specified by enclosing the pattern in parentheses (e.g.
<code class="docutils literal notranslate"><span class="pre">([Mm]akefile)</span></code>). A prefixed plus (’<code class="docutils literal notranslate"><span class="pre">+</span></code>’) sign is for adding, and
minus (’<code class="docutils literal notranslate"><span class="pre">-</span></code>’) is for removing. No prefix means replacing the map of <em><LANG></em>.</p>
<p>Unlike <code class="docutils literal notranslate"><span class="pre">--langmap</span></code>, <em><extension></em> (or <em><pattern></em>) is not a list.
<code class="docutils literal notranslate"><span class="pre">--map-<LANG></span></code> takes one extension (or pattern). However,
the option can be specified with different arguments multiple times
in a command line.</p>
</dd>
</dl>
</section>
<section id="tags-file-contents-options">
<span id="option-tags-file-contents"></span><h3>Tags File Contents Options<a class="headerlink" href="#tags-file-contents-options" title="Permalink to this headline">¶</a></h3>
<p>See “<a class="reference internal" href="#id1">TAG ENTRIES</a>” about fields, kinds, roles, and extras.</p>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--excmd=(number|pattern|mix|combine)</span></code></dt><dd><p>Determines the type of <code class="docutils literal notranslate"><span class="pre">EX</span></code> command used to locate tags in the source
file. [Ignored in etags mode]</p>
<p>The valid values for type (either the entire word or the first letter
is accepted) are:</p>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">number</span></code></dt><dd><p>Use only line numbers in the tag file for locating tags. This has
four advantages:</p>
<ol class="arabic simple">
<li><p>Significantly reduces the size of the resulting tag file.</p></li>
<li><p>Eliminates failures to find tags because the line defining the
tag has changed, causing the pattern match to fail (note that
some editors, such as <code class="docutils literal notranslate"><span class="pre">vim</span></code>, are able to recover in many such
instances).</p></li>
<li><p>Eliminates finding identical matching, but incorrect, source
lines (see “<a class="reference internal" href="#bugs">BUGS</a>”).</p></li>
<li><p>Retains separate entries in the tag file for lines which are
identical in content. In pattern mode, duplicate entries are
dropped because the search patterns they generate are identical,
making the duplicate entries useless.</p></li>
</ol>
<p>However, this option has one significant drawback: changes to the
source files can cause the line numbers recorded in the tag file
to no longer correspond to the lines in the source file, causing
jumps to some tags to miss the target definition by one or more
lines. Basically, this option is best used when the source code
to which it is applied is not subject to change. Selecting this
option type causes the following options to be ignored: <code class="docutils literal notranslate"><span class="pre">-B</span></code>, <code class="docutils literal notranslate"><span class="pre">-F</span></code>.</p>
<p><code class="docutils literal notranslate"><span class="pre">number</span></code> type is ignored in Xref and JSON output formats. Use
<code class="docutils literal notranslate"><span class="pre">--_xformat="...%n"</span></code> for Xref output format, or <code class="docutils literal notranslate"><span class="pre">--fields=+n-P</span></code> for
JSON output format.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">pattern</span></code></dt><dd><p>Use only search patterns for all tags, rather than the line numbers
usually used for macro definitions. This has the advantage of
not referencing obsolete line numbers when lines have been added or
removed since the tag file was generated.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">mixed</span></code></dt><dd><p>In this mode, patterns are generally used with a few exceptions.
For C, line numbers are used for macro definition tags. For Fortran, line numbers
are used for common blocks because their corresponding source lines
are generally identical, making pattern searches useless
for finding all matches.</p>
<p>This was the default format generated by the original ctags and is,
therefore, retained as the default for this option.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">combine</span></code></dt><dd><p>Concatenate the line number and pattern with a semicolon in between.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-n</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--excmd=number</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-N</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--excmd=pattern</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--extras=[+|-][<flags>|*]</span></code></dt><dd><p>Specifies whether to include extra tag entries for certain kinds of
information. See also “<a class="reference internal" href="#extras">Extras</a>” subsection to know what are extras.</p>
<p>The parameter <em><flags></em> is a set of one-letter flags (and/or long-name flags), each
representing one kind of extra tag entry to include in the tag file.
If flags is preceded by either the ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ character, the effect of
each flag is added to, or removed from, those currently enabled;
otherwise the flags replace any current settings. All entries are
included if ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ is given.</p>
<p>This <code class="docutils literal notranslate"><span class="pre">--extras=</span></code> option is for controlling extras common in all
languages (or language-independent extras). Universal Ctags also
supports language-specific extras. (See “<a class="reference internal" href="#language-specific-fields-and-extras">Language-specific fields and
extras</a>” about the concept). Use <code class="docutils literal notranslate"><span class="pre">--extras-<LANG>=</span></code> option for
controlling them.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--extras-(<LANG>|all)=[+|-][<flags>|*]</span></code></dt><dd><p>Specifies whether to include extra tag entries for certain kinds of
information for language <em><LANG></em>. Universal Ctags
introduces language-specific extras. See “<a class="reference internal" href="#language-specific-fields-and-extras">Language-specific fields and
extras</a>” about the concept. This option is for controlling them.</p>
<p>Specifies <code class="docutils literal notranslate"><span class="pre">all</span></code> as <em><LANG></em> to apply the parameter <em><flags></em> to all
languages; all extras are enabled with specifying ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ as the
parameter flags. If specifying nothing as the parameter flags
(<code class="docutils literal notranslate"><span class="pre">--extras-all=</span></code>), all extras are disabled. These two combinations
are useful for testing.</p>
<p>Check the output of the <code class="docutils literal notranslate"><span class="pre">--list-extras=<LANG></span></code> option for the
extras of specific language <em><LANG></em>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--fields=[+|-][<flags>|*]</span></code></dt><dd><p>Specifies which language-independent fields are to be included in the tag
entries. Language-independent fields are extension fields which are common
in all languages. See “<a class="reference internal" href="#tag-file-format">TAG FILE FORMAT</a>” section, and “<a class="reference internal" href="#extension-fields">Extension fields</a>”
subsection, for details of extension fields.</p>
<p>The parameter <em><flags></em> is a set of one-letter or long-name flags,
each representing one type of extension field to include.
Each flag or group of flags may be preceded by either ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ to add it
to the default set, or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ to exclude it. In the absence of any
preceding ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ sign, only those fields explicitly listed in flags
will be included in the output (i.e. overriding the default set). All
fields are included if ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ is given.</p>
<p>This option is ignored if the
option <code class="docutils literal notranslate"><span class="pre">--format=1</span></code> (legacy tag file format) has been specified.</p>
<p>Use <code class="docutils literal notranslate"><span class="pre">--fields-<LANG>=</span></code> option for controlling language-specific fields.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--fields-(<LANG>|all)=[+|-][<flags>|*]</span></code></dt><dd><p>Specifies which language-specific fields are to be included in
the tag entries. Universal Ctags
supports language-specific fields. (See “<a class="reference internal" href="#language-specific-fields-and-extras">Language-specific fields and
extras</a>” about the concept).</p>
<p>Specify <code class="docutils literal notranslate"><span class="pre">all</span></code> as <em><LANG></em> to apply the parameter <em><flags></em> to all
languages; all fields are enabled with specifying ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ as the
parameter flags. If specifying nothing as the parameter <em><flags></em>
(i.e. <code class="docutils literal notranslate"><span class="pre">--fields-all=</span></code>), all fields are disabled. These two combinations
are useful for testing.</p>
<p>See the description of <code class="docutils literal notranslate"><span class="pre">--fields=[+|-][<flags>|*]</span></code> about <em><flags></em>.</p>
<p>Use <code class="docutils literal notranslate"><span class="pre">--fields=</span></code> option for controlling language-independent fields.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--kinds-(<LANG>|all)=[+|-](<kinds>|*)</span></code></dt><dd><p>Specifies a list of language-specific <em><kinds></em> of tags (or kinds) to
include in the output file for a particular language, where <em><LANG></em> is
case-insensitive and is one of the built-in language names (see the
<code class="docutils literal notranslate"><span class="pre">--list-languages</span></code> option for a complete list).</p>
<p>The parameter <em><kinds></em> is a group
of one-letter or long-name flags designating kinds of tags (particular to the language)
to either include or exclude from the output. The specific sets of
flags recognized for each language, their meanings and defaults may be
list using the <code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code> option.</p>
<p>Each letter or group of letters
may be preceded by either ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ to add it to, or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ to remove it from,
the default set. In the absence of any preceding ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ or ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ sign, only
those kinds explicitly listed in kinds will be included in the output
(i.e. overriding the default for the specified language).</p>
<p>Specify ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ as the parameter to include all kinds implemented
in <em><LANG></em> in the output. Furthermore if <code class="docutils literal notranslate"><span class="pre">all</span></code> is given as <em><LANG></em>,
specification of the parameter <code class="docutils literal notranslate"><span class="pre">kinds</span></code> affects all languages defined
in ctags. Giving <code class="docutils literal notranslate"><span class="pre">all</span></code> makes sense only when ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ or
‘<code class="docutils literal notranslate"><span class="pre">F</span></code>’ is given as the parameter <code class="docutils literal notranslate"><span class="pre">kinds</span></code>.</p>
<p>As an example for the C language, in order to add prototypes and
external variable declarations to the default set of tag kinds,
but exclude macros, use <code class="docutils literal notranslate"><span class="pre">--kinds-c=+px-d</span></code>; to include only tags for
functions, use <code class="docutils literal notranslate"><span class="pre">--kinds-c=f</span></code>.</p>
<p>Some kinds of C and C++ languages are synchronized; enabling
(or disabling) a kind in one language enables the kind having
the same one-letter and long-name in the other language. See also the
description of <code class="docutils literal notranslate"><span class="pre">MASTER</span></code> column of <code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code>.</p>
</dd>
</dl>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--pattern-length-limit=<N></span></code></dt><dd><p>Truncate patterns of tag entries after <em><N></em> characters. Disable by setting to 0
(default is 96).</p>
<p>An input source file with long lines and multiple tag matches per
line can generate an excessively large tags file with an
unconstrained pattern length. For example, running ctags on a
minified JavaScript source file often exhibits this behavior.</p>
<p>The truncation avoids cutting in the middle of a UTF-8 code point
spanning multiple bytes to prevent writing invalid byte sequences from
valid input files. This handling allows for an extra 3 bytes above the
configured limit in the worse case of a 4 byte code point starting
right before the limit. Please also note that this handling is fairly
naive and fast, and although it is resistant against any input, it
requires a valid input to work properly; it is not guaranteed to work
as the user expects when dealing with partially invalid UTF-8 input.
This also partially affect non-UTF-8 input, if the byte sequence at
the truncation length looks like a multibyte UTF-8 sequence. This
should however be rare, and in the worse case will lead to including
up to an extra 3 bytes above the limit.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--pseudo-tags=[+|-](<pseudo-tag>|*)</span></code></dt><dd><p>Enable/disable emitting pseudo-tag named <em><pseudo-tag></em>.
If ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ is given, enable/disable emitting all pseudo-tags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--put-field-prefix</span></code></dt><dd><p>Put <code class="docutils literal notranslate"><span class="pre">UCTAGS</span></code> as prefix for the name of fields newly introduced in
Universal Ctags.</p>
<p>Some fields are newly introduced in Universal Ctags and more will
be introduced in the future. Other tags generators may also
introduce their specific fields.</p>
<p>In such a situation, there is a concern about conflicting field
names; mixing tags files generated by multiple tags generators
including Universal Ctags is difficult. This option provides a
workaround for such station.</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --fields<span class="o">=</span><span class="s1">'{line}{end}'</span> -o - hello.c
<span class="go">main hello.c /^main(int argc, char **argv)$/;" f line:3 end:6</span>
<span class="gp">$ </span>ctags --put-field-prefix --fields<span class="o">=</span><span class="s1">'{line}{end}'</span> -o - hello.c
<span class="go">main hello.c /^main(int argc, char **argv)$/;" f line:3 UCTAGSend:6</span>
</pre></div>
</div>
<p>In the above example, the prefix is put to <code class="docutils literal notranslate"><span class="pre">end</span></code> field which is
newly introduced in Universal Ctags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--roles-(<LANG>|all).(<kind>|all)=[+|-][<roles>|*]</span></code></dt><dd><p>Specifies a list of kind-specific roles of tags to include in the
output file for a particular language.
<em><kind></em> specifies the kind where the <em><roles></em> are defined.
<em><LANG></em> specifies the language where the kind is defined.
Each role in <em><roles></em> must be surrounded by braces (e.g. <code class="docutils literal notranslate"><span class="pre">{system}</span></code>
for a role named “system”).</p>
<p>Like <code class="docutils literal notranslate"><span class="pre">--kinds-<LANG></span></code> option, ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ is for adding the role to the
list, and ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ is for removing from the list. ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ is for including
all roles of the kind to the list. The option with no argument
makes the list empty.</p>
<p>Both a one-letter flag or a long name flag surrounded by braces are
acceptable for specifying a kind (e.g. <code class="docutils literal notranslate"><span class="pre">--roles-C.h=+{system}{local}</span></code>
or <code class="docutils literal notranslate"><span class="pre">--roles-C.{header}=+{system}{local}</span></code>). ‘<code class="docutils literal notranslate"><span class="pre">*</span></code>’ can be used for <em><KIND></em>
only for adding/removing all roles of all kinds in a language to/from
the list (e.g. <code class="docutils literal notranslate"><span class="pre">--roles-C.*=*</span></code> or <code class="docutils literal notranslate"><span class="pre">--roles-C.*=</span></code>).</p>
<p><code class="docutils literal notranslate"><span class="pre">all</span></code> can be used for <em><LANG></em> only for adding/removing all roles of
all kinds in all languages to/from the list
(e.g. <code class="docutils literal notranslate"><span class="pre">--roles-all.*=*</span></code> or <code class="docutils literal notranslate"><span class="pre">--roles-all.*=</span></code>).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--tag-relative=(yes|no|always|never)</span></code></dt><dd><p>Specifies how the file paths recorded in the tag file.
The default is <code class="docutils literal notranslate"><span class="pre">yes</span></code> when running in etags mode (see
the <code class="docutils literal notranslate"><span class="pre">-e</span></code> option), <code class="docutils literal notranslate"><span class="pre">no</span></code> otherwise.</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">yes</span></code></dt><dd><p>indicates that the file paths recorded in the tag file should be
<em>relative to the directory containing the tag file</em>
unless the files supplied on the command line
are specified with absolute paths.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">no</span></code></dt><dd><p>indicates that the file paths recorded in the tag file should be
<em>relative to the current directory</em>
unless the files supplied on the command line
are specified with absolute paths.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">always</span></code></dt><dd><p>indicates the recorded file paths should be relative
even if source file names are passed in with absolute paths.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">never</span></code></dt><dd><p>indicates the recorded file paths should be absolute
even if source file names are passed in with relative paths.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--use-slash-as-filename-separator[=(yes|no)]</span></code></dt><dd><p>Uses slash (’<code class="docutils literal notranslate"><span class="pre">/</span></code>’) character as filename separators instead of backslash
(’<code class="docutils literal notranslate"><span class="pre">\</span></code>’) character when printing <code class="docutils literal notranslate"><span class="pre">input:</span></code> field.
The default is <code class="docutils literal notranslate"><span class="pre">yes</span></code> for the default “u-ctags” output format, and
<code class="docutils literal notranslate"><span class="pre">no</span></code> for the other formats.</p>
<p>This option is available on MS Windows only.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-B</span></code></dt><dd><p>Use backward searching patterns (e.g. <code class="docutils literal notranslate"><span class="pre">?pattern?</span></code>). [Ignored in etags mode]</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-F</span></code></dt><dd><p>Use forward searching patterns (e.g. <code class="docutils literal notranslate"><span class="pre">/pattern/</span></code>) (default). [Ignored
in etags mode]</p>
</dd>
</dl>
</section>
<section id="option-file-options">
<h3>Option File Options<a class="headerlink" href="#option-file-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--options=<pathname></span></code></dt><dd><p>Read additional options from file or directory.</p>
<p>ctags searches <em><pathname></em> in the optlib path list
first. If ctags cannot find a file or directory
in the list, ctags reads a file or directory
at the specified <em><pathname></em>.</p>
<p>If a file is specified, it should contain one option per line. If
a directory is specified, files suffixed with <code class="docutils literal notranslate"><span class="pre">.ctags</span></code> under it
are read in alphabetical order.</p>
<p>As a special case, if <code class="docutils literal notranslate"><span class="pre">--options=NONE</span></code> is specified as the first
option on the command line, preloading is disabled; the option
will disable the automatic reading of any configuration options
from a file (see “<a class="reference internal" href="#files">FILES</a>”).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--options-maybe=<pathname></span></code></dt><dd><p>Same as <code class="docutils literal notranslate"><span class="pre">--options</span></code> but doesn’t cause an error if file
(or directory) specified with <em><pathname></em> doesn’t exist.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--optlib-dir=[+]<directory></span></code></dt><dd><p>Add an optlib <em><directory></em> to or reset the optlib path list.
By default, the optlib path list is empty.</p>
</dd>
</dl>
</section>
<section id="optlib-options">
<h3>optlib Options<a class="headerlink" href="#optlib-options" title="Permalink to this headline">¶</a></h3>
<p>See <a class="reference internal" href="ctags-optlib.7.html#ctags-optlib-7"><span class="std std-ref">ctags-optlib(7)</span></a> for details of each option.</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">--kinddef-<LANG>=<letter>,<name>,<description></span></code></dt><dd><p>Define a kind for <em><LANG></em>.
Don’t be confused this with <code class="docutils literal notranslate"><span class="pre">--kinds-<LANG></span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--langdef=<name></span></code></dt><dd><p>Defines a new user-defined language, <em><name></em>, to be parsed with regular
expressions.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--mline-regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></code></dt><dd><p>Define multi-line regular expression for locating tags in specific language.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></code></dt><dd><p>Define single-line regular expression for locating tags in specific language.</p>
</dd>
</dl>
</section>
<section id="language-specific-options">
<span id="option-lang-specific"></span><h3>Language Specific Options<a class="headerlink" href="#language-specific-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--if0[=(yes|no)]</span></code></dt><dd><p>Indicates a preference as to whether code within an “<code class="docutils literal notranslate"><span class="pre">#if</span> <span class="pre">0</span></code>” branch of a
preprocessor conditional should be examined for non-macro tags (macro
tags are always included). Because the intent of this construct is to
disable code, the default value of this option is <code class="docutils literal notranslate"><span class="pre">no</span></code> (disabled).</p>
<p>Note that this
indicates a preference only and does not guarantee skipping code within
an “<code class="docutils literal notranslate"><span class="pre">#if</span> <span class="pre">0</span></code>” branch, since the fall-back algorithm used to generate
tags when preprocessor conditionals are too complex follows all branches
of a conditional.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--line-directives[=(yes|no)]</span></code></dt><dd><p>Specifies whether <code class="docutils literal notranslate"><span class="pre">#line</span></code> directives should be recognized. These are
present in the output of a preprocessor and contain the line number, and
possibly the file name, of the original source file(s) from which the
preprocessor output file was generated. This option is off by default.</p>
<p>When enabled, this option will
cause ctags to generate tag entries marked with the
file names and line numbers of their locations original source file(s),
instead of their actual locations in the preprocessor output. The actual
file names placed into the tag file will have the same leading path
components as the preprocessor output file, since it is assumed that
the original source files are located relative to the preprocessor
output file (unless, of course, the <code class="docutils literal notranslate"><span class="pre">#line</span></code> directive specifies an
absolute path).</p>
<p>Note: This option is generally
only useful when used together with the <code class="docutils literal notranslate"><span class="pre">--excmd=number</span></code> (<code class="docutils literal notranslate"><span class="pre">-n</span></code>) option.
Also, you may have to use either the <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> or <code class="docutils literal notranslate"><span class="pre">--language-force</span></code> option
if the extension of the preprocessor output file is not known to
ctags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-D</span> <span class="pre"><macro>=<definition></span></code></dt><dd><p>Defines a C preprocessor <em><macro></em>. This emulates the behavior of the
corresponding gcc option. All types of macros are supported,
including the ones with parameters and variable arguments.
Stringification, token pasting and recursive macro expansion are also
supported.
This extends the function provided by <code class="docutils literal notranslate"><span class="pre">-I</span></code> option.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-h</span> <span class="pre">(<list>|default)</span></code></dt><dd><p>Specifies a <em><list></em> of file extensions, separated by periods, which are
to be interpreted as include (or header) files. To indicate files having
no extension, use a period not followed by a non-period character
(e.g. ‘<code class="docutils literal notranslate"><span class="pre">.</span></code>’, <code class="docutils literal notranslate"><span class="pre">..x</span></code>, <code class="docutils literal notranslate"><span class="pre">.x.</span></code>).</p>
<p>This option only affects how the scoping of
particular kinds of tags are interpreted (i.e. whether or not they are
considered as globally visible or visible only within the file in which
they are defined); it does not map the extension to any particular
language. Any tag which is located in a non-include file and cannot be
seen (e.g. linked to) from another file is considered to have file-limited
(e.g. static) scope. No kind of tag appearing in an include file
will be considered to have file-limited scope.</p>
<p>If the first character in the list is ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’, then the extensions in the list will be
appended to the current list; otherwise, the list will replace the
current list. See, also, the <code class="docutils literal notranslate"><span class="pre">fileScope</span></code>/<code class="docutils literal notranslate"><span class="pre">F</span></code> flag of <code class="docutils literal notranslate"><span class="pre">--extras</span></code> option.</p>
<p>The default list is
<code class="docutils literal notranslate"><span class="pre">.h.H.hh.hpp.hxx.h++.inc.def</span></code>. To restore the default list, specify “<code class="docutils literal notranslate"><span class="pre">-h</span>
<span class="pre">default</span></code>”.</p>
<p>Note that if an extension supplied to this option is not
already mapped to a particular language (see “<a class="reference internal" href="#determining-file-language">Determining file language</a>”, above),
you will also need to use either the <code class="docutils literal notranslate"><span class="pre">--map-<LANG></span></code>, <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> or
<code class="docutils literal notranslate"><span class="pre">--language-force</span></code> option.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre"><identifier-list></span></code></dt><dd><p>Specifies a <em><identifier-list></em> of identifiers which are to be specially handled while
parsing C and C++ source files. This option is specifically provided
to handle special cases arising through the use of preprocessor macros.
When the identifiers listed are simple identifiers, these identifiers
will be ignored during parsing of the source files.</p>
<p>If an identifier is
suffixed with a ‘<code class="docutils literal notranslate"><span class="pre">+</span></code>’ character (i.e. “<code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre">FOO+</span></code>”), ctags will also
ignore any parenthesis-enclosed argument list which may immediately
follow the identifier in the source files. See the example of “<code class="docutils literal notranslate"><span class="pre">-I</span>
<span class="pre">MODULE_VERSION+</span></code>” below.</p>
<p>If two identifiers are
separated with the ‘<code class="docutils literal notranslate"><span class="pre">=</span></code>’ character (i.e. <code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre">FOO=BAR</span></code>), the first identifiers is replaced by
the second identifiers for parsing purposes. The list of identifiers may
be supplied directly on the command line or read in from a separate file.
See the example of “<code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre">CLASS=class</span></code>” below.</p>
<p>If the first character of <em><identifier-list></em> is ‘<code class="docutils literal notranslate"><span class="pre">@</span></code>’, ‘<code class="docutils literal notranslate"><span class="pre">.</span></code>’ or a pathname
separator (’<code class="docutils literal notranslate"><span class="pre">/</span></code>’ or ‘<code class="docutils literal notranslate"><span class="pre">\</span></code>’), or the first two characters specify a drive
letter (e.g. <code class="docutils literal notranslate"><span class="pre">C:</span></code>), the parameter <em><identifier-list></em> will be interpreted as
a filename from which to read a list of identifiers, one per input line.</p>
<p>Otherwise, <em><identifier-list></em> is a list of identifiers (or identifier
pairs) to be specially handled, each delimited by either a comma or
by white space (in which case the list should be quoted to keep the
entire list as one command line argument).</p>
<p>Multiple <code class="docutils literal notranslate"><span class="pre">-I</span></code> options may be
supplied. To clear the list of ignore identifiers, supply a single
dash (’<code class="docutils literal notranslate"><span class="pre">-</span></code>’) for <em><identifier-list></em>.</p>
<p>This feature is useful when preprocessor macros are used in such a way
that they cause syntactic confusion due to their presence. Indeed,
this is the best way of working around a number of problems caused by
the presence of syntax-busting macros in source files (see “<a class="reference internal" href="#caveats">CAVEATS</a>”).
Some examples will illustrate this point.</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="kt">int</span> <span class="n">foo</span> <span class="n">ARGDECL4</span><span class="p">(</span><span class="kt">void</span> <span class="o">*</span><span class="p">,</span> <span class="n">ptr</span><span class="p">,</span> <span class="kt">long</span> <span class="kt">int</span><span class="p">,</span> <span class="n">nbytes</span><span class="p">)</span>
</pre></div>
</div>
<p>In the above example, the macro <code class="docutils literal notranslate"><span class="pre">ARGDECL4</span></code> would be mistakenly
interpreted to be the name of the function instead of the correct name
of <code class="docutils literal notranslate"><span class="pre">foo</span></code>. Specifying “<code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre">ARGDECL4</span></code>” results in the correct behavior.</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="cm">/* creates an RCS version string in module */</span>
<span class="n">MODULE_VERSION</span><span class="p">(</span><span class="s">"$Revision$"</span><span class="p">)</span>
</pre></div>
</div>
<p>In the above example the macro invocation looks too much like a function
definition because it is not followed by a semicolon (indeed, it
could even be followed by a global variable definition that would look
much like a K&R style function parameter declaration). In fact, this
seeming function definition could possibly even cause the rest of the
file to be skipped over while trying to complete the definition.
Specifying “<code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre">MODULE_VERSION+</span></code>” would avoid such a problem.</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="n">CLASS</span> <span class="n">Example</span> <span class="p">{</span>
<span class="c1">// your content here</span>
<span class="p">};</span>
</pre></div>
</div>
<p>The example above uses <code class="docutils literal notranslate"><span class="pre">CLASS</span></code> as a preprocessor macro which expands to
something different for each platform. For instance <code class="docutils literal notranslate"><span class="pre">CLASS</span></code> may be
defined as <code class="docutils literal notranslate"><span class="pre">class</span> <span class="pre">__declspec(dllexport)</span></code> on Win32 platforms and simply
<code class="docutils literal notranslate"><span class="pre">class</span></code> on UNIX. Normally, the absence of the C++ keyword <code class="docutils literal notranslate"><span class="pre">class</span></code>
would cause the source file to be incorrectly parsed. Correct behavior
can be restored by specifying “<code class="docutils literal notranslate"><span class="pre">-I</span> <span class="pre">CLASS=class</span></code>”.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--param-<LANG>:<name>=<argument></span></code></dt><dd><p>Set a <em><LANG></em> specific parameter, a parameter specific to the <em><LANG></em>.</p>
<p>Available parameters can be listed with <code class="docutils literal notranslate"><span class="pre">--list-params</span></code>.</p>
</dd>
</dl>
</section>
<section id="listing-options">
<span id="option-listing"></span><h3>Listing Options<a class="headerlink" href="#listing-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--list-aliases[=(<language>|all)]</span></code></dt><dd><p>Lists the aliases for either the specified <em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code>
languages, and then exits.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.
The aliases are used when heuristically testing a language parser for a
source file.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-excludes</span></code></dt><dd><p>Lists the current exclusion patterns used to exclude files.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-extras[=(<language>|all)]</span></code></dt><dd><p>Lists the extras recognized for either the specified <em><language></em> or
<code class="docutils literal notranslate"><span class="pre">all</span></code> languages. See “<a class="reference internal" href="#extras">Extras</a>” subsection to know what are extras.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
<p>An extra can be enabled or disabled with <code class="docutils literal notranslate"><span class="pre">--extras=</span></code> for common
extras in all languages, or <code class="docutils literal notranslate"><span class="pre">--extras-<LANG>=</span></code> for the specified
language. These option takes one-letter flag or long-name flag as a parameter
for specifying an extra.</p>
<p>The meaning of columns in output are as follows:</p>
<dl class="simple">
<dt>LETTER</dt><dd><p>One-letter flag. ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ means the extra does not have one-letter flag.</p>
</dd>
<dt>NAME</dt><dd><p>Long-name flag. The long-name is used in <code class="docutils literal notranslate"><span class="pre">extras</span></code> field.</p>
</dd>
<dt>ENABLED</dt><dd><p>Whether the extra is enabled or not. It takes <code class="docutils literal notranslate"><span class="pre">yes</span></code> or <code class="docutils literal notranslate"><span class="pre">no</span></code>.</p>
</dd>
<dt>LANGUAGE</dt><dd><p>The name of language if the extra is owned by a parser.
<code class="docutils literal notranslate"><span class="pre">NONE</span></code> means the extra is common in parsers.</p>
</dd>
<dt>DESCRIPTION</dt><dd><p>Human readable description for the extra.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-features</span></code></dt><dd><p>Lists the compiled features.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-fields[=(<language>|all)]</span></code></dt><dd><p>Lists the fields recognized for either the specified <em><language></em> or
<code class="docutils literal notranslate"><span class="pre">all</span></code> languages. See “<a class="reference internal" href="#extension-fields">Extension fields</a>” subsection to know what are fields.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
<p>The meaning of columns are as follows:</p>
<dl>
<dt>LETTER</dt><dd><p>One-letter flag. ‘<code class="docutils literal notranslate"><span class="pre">-</span></code>’ means the field does not have one-letter flag.</p>
</dd>
<dt>NAME</dt><dd><p>Long-name of field.</p>
</dd>
<dt>ENABLED</dt><dd><p>Whether the field is enabled or not. It takes <code class="docutils literal notranslate"><span class="pre">yes</span></code> or <code class="docutils literal notranslate"><span class="pre">no</span></code>.</p>
</dd>
<dt>LANGUAGE</dt><dd><p>The name of language if the field is owned by a parser.
<code class="docutils literal notranslate"><span class="pre">NONE</span></code> means that the field is a language-independent field which is
common in all languages.</p>
</dd>
<dt>JSTYPE</dt><dd><p>JSON type used in printing the value of field when <code class="docutils literal notranslate"><span class="pre">--output-format=json</span></code>
is specified. See <a class="reference internal" href="ctags-client-tools.7.html#ctags-client-tools-7"><span class="std std-ref">ctags-client-tools(7)</span></a>.</p>
</dd>
<dt>FIXED</dt><dd><p>Whether this field can be disabled or not in tags output.</p>
<p>Some fields are printed always in tags output.
They have <code class="docutils literal notranslate"><span class="pre">yes</span></code> as the value for this column.</p>
<p>Unlike the tag output mode, JSON output mode allows disabling
any fields.</p>
</dd>
<dt>OP</dt><dd><p>How this field can be accessed from optscript code.
This field is for Universal Ctags developers.</p>
</dd>
<dt>DESCRIPTION</dt><dd><p>Human readable description for the field.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-kinds[=(<language>|all)]</span></code></dt><dd><p>Subset of <code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code>. This option is kept for
backward-compatibility with Exuberant Ctags.</p>
<p>This option prints only LETTER, DESCRIPTION, and ENABLED fields
of <code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code> output. However, the presentation of
ENABLED column is different from that of <code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code>
option; <code class="docutils literal notranslate"><span class="pre">[off]</span></code> follows after description if the kind is disabled,
and nothing follows if enabled. The most of all kinds are enabled
by default.</p>
<p>The critical weakness of this option is that this option does not
print the name of kind. Universal Ctags introduces
<code class="docutils literal notranslate"><span class="pre">--list-kinds-full</span></code> because it considers that names are
important.</p>
<p>This option does not work with <code class="docutils literal notranslate"><span class="pre">--machinable</span></code> nor
<code class="docutils literal notranslate"><span class="pre">--with-list-header</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-kinds-full[=(<language>|all)]</span></code></dt><dd><p>Lists the tag kinds recognized for either the specified <em><language></em>
or <code class="docutils literal notranslate"><span class="pre">all</span></code> languages, and then exits. See “<a class="reference internal" href="#kinds">Kinds</a>” subsection to
learn what kinds are.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
<p>Each kind of tag recorded in the tag file is represented by a
one-letter flag, or a long-name flag. They are also used to filter the tags
placed into the output through use of the <code class="docutils literal notranslate"><span class="pre">--kinds-<LANG></span></code>
option.</p>
<p>The meaning of columns are as follows:</p>
<dl>
<dt>LANGUAGE</dt><dd><p>The name of language having the kind.</p>
</dd>
<dt>LETTER</dt><dd><p>One-letter flag. This must be unique in a language.</p>
</dd>
<dt>NAME</dt><dd><p>The long-name flag of the kind. This can be used as the alternative
to the one-letter flag described above. If enabling <code class="docutils literal notranslate"><span class="pre">K</span></code> field with
<code class="docutils literal notranslate"><span class="pre">--fields=+K</span></code>, ctags uses long-names instead of
one-letters in tags output. To enable/disable a kind with
<code class="docutils literal notranslate"><span class="pre">--kinds-<LANG></span></code> option, long-name surrounded by braces instead
of one-letter. See “<a class="reference internal" href="#letters-and-names">Letters and names</a>” for details. This must be
unique in a language.</p>
</dd>
<dt>ENABLED</dt><dd><p>Whether the kind is enabled or not. It takes <code class="docutils literal notranslate"><span class="pre">yes</span></code> or <code class="docutils literal notranslate"><span class="pre">no</span></code>.</p>
</dd>
<dt>REFONLY</dt><dd><p>Whether the kind is specialized for reference tagging or not.
If the column is <code class="docutils literal notranslate"><span class="pre">yes</span></code>, the kind is for reference tagging, and
it is never used for definition tagging. See also “<a class="reference internal" href="#id1">TAG ENTRIES</a>”.</p>
</dd>
<dt>NROLES</dt><dd><p>The number of roles this kind has. See also “<a class="reference internal" href="#roles">Roles</a>”.</p>
</dd>
<dt>MASTER</dt><dd><p>The master parser controlling enablement of the kind.
A kind belongs to a language (owner) in Universal Ctags;
enabling and disabling a kind in a language has no effect on
a kind in another language even if both kinds has the
same one-letter flag and/or the same long-name flag. In other words,
the namespace of kinds are separated by language.</p>
<p>However, Exuberant Ctags does not separate the kinds of C and
C++. Enabling/disabling kindX in C language enables/disables a
kind in C++ language having the same long-name flag with kindX. To
emulate this behavior in Universal Ctags, a concept named
<em>master parser</em> is introduced. Enabling/disabling some kinds
are synchronized under the control of a master language.</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --kinds-C<span class="o">=</span>+<span class="s1">'{local}'</span> --list-kinds-full <span class="se">\</span>
<span class="go"> | grep -E '^(#|C\+\+ .* local)'</span>
<span class="gp">#</span>LANGUAGE LETTER NAME ENABLED REFONLY NROLES MASTER DESCRIPTION
<span class="go">C++ l local yes no 0 C local variables</span>
<span class="gp">$ </span>ctags --kinds-C<span class="o">=</span>-<span class="s1">'{local}'</span> --list-kinds-full <span class="se">\</span>
<span class="go"> | grep -E '^(#|C\+\+ .* local)'</span>
<span class="gp">#</span>LANGUAGE LETTER NAME ENABLED REFONLY NROLES MASTER DESCRIPTION
<span class="go">C++ l local no no 0 C local variables</span>
</pre></div>
</div>
<p>You see <code class="docutils literal notranslate"><span class="pre">ENABLED</span></code> field of <code class="docutils literal notranslate"><span class="pre">local</span></code> kind of C++ language is changed
Though <code class="docutils literal notranslate"><span class="pre">local</span></code> kind of C language is enabled/disabled. If you swap the languages, you
see the same result.</p>
</dd>
<dt>DESCRIPTION</dt><dd><p>Human readable description for the kind.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-languages</span></code></dt><dd><p>Lists the names of the languages understood by ctags,
and then exits. These language names are case insensitive and may be
used in many other options like <code class="docutils literal notranslate"><span class="pre">--language-force</span></code>,
<code class="docutils literal notranslate"><span class="pre">--languages</span></code>, <code class="docutils literal notranslate"><span class="pre">--kinds-<LANG></span></code>, <code class="docutils literal notranslate"><span class="pre">--regex-<LANG></span></code>, and so on.</p>
<p>Each language listed is disabled if followed by <code class="docutils literal notranslate"><span class="pre">[disabled]</span></code>.
To use the parser for such a language, specify the language as an
argument of <code class="docutils literal notranslate"><span class="pre">--languages=+</span></code> option.</p>
<p><code class="docutils literal notranslate"><span class="pre">--machinable</span></code> and <code class="docutils literal notranslate"><span class="pre">--with-list-header</span></code> options are ignored if they are
specified with this option.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-map-extensions[=(<language>|all)]</span></code></dt><dd><p>Lists the file extensions which associate a file
name with a language for either the specified <em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code>
languages, and then exits.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-map-patterns[=(<language>|all)]</span></code></dt><dd><p>Lists the file name patterns which associate a file
name with a language for either the specified <em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code>
languages, and then exits.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-maps[=(<language>|all)]</span></code></dt><dd><p>Lists file name patterns and the file extensions which associate a file
name with a language for either the specified <em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code>
languages, and then exits.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
<p>To list the file extensions or file name patterns individually, use
<code class="docutils literal notranslate"><span class="pre">--list-map-extensions</span></code> or <code class="docutils literal notranslate"><span class="pre">--list-map-patterns</span></code> option.
See the <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> option, and “<a class="reference internal" href="#determining-file-language">Determining file language</a>”, above.</p>
<p>This option does not work with <code class="docutils literal notranslate"><span class="pre">--machinable</span></code> nor
<code class="docutils literal notranslate"><span class="pre">--with-list-header</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-mline-regex-flags</span></code></dt><dd><p>Output list of flags which can be used in a multiline regex parser
definition.
See <a class="reference internal" href="ctags-optlib.7.html#ctags-optlib-7"><span class="std std-ref">ctags-optlib(7)</span></a>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-params[=(<language>|all)]</span></code></dt><dd><p>Lists the parameters for either the specified <em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code>
languages, and then exits.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-pseudo-tags</span></code></dt><dd><p>Output list of pseudo-tags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-regex-flags</span></code></dt><dd><p>Lists the flags that can be used in <code class="docutils literal notranslate"><span class="pre">--regex-<LANG></span></code> option.
See <a class="reference internal" href="ctags-optlib.7.html#ctags-optlib-7"><span class="std std-ref">ctags-optlib(7)</span></a>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-roles[=(<language>|all)[.(<kind-specs>|*)]]</span></code></dt><dd><p>List the roles for either the specified <em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code> languages.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
<p>If the parameter <em><kindspecs></em> is given after the parameter
<em><language></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code> with concatenating with ‘<code class="docutils literal notranslate"><span class="pre">.</span></code>’, list only roles
defined in the kinds. Both one-letter flags and long name flags surrounded
by braces are acceptable as the parameter <em><kindspecs></em>.</p>
<p>The meaning of columns are as follows:</p>
<dl class="simple">
<dt>LANGUAGE</dt><dd><p>The name of language having the role.</p>
</dd>
<dt>KIND(L/N)</dt><dd><p>The one-letter flag and the long-name flag of kind having the role.</p>
</dd>
<dt>NAME</dt><dd><p>The long-name flag of the role.</p>
</dd>
<dt>ENABLED</dt><dd><p>Whether the kind is enabled or not. It takes <code class="docutils literal notranslate"><span class="pre">yes</span></code> or <code class="docutils literal notranslate"><span class="pre">no</span></code>.</p>
</dd>
<dt>DESCRIPTION</dt><dd><p>Human readable description for the role.</p>
</dd>
</dl>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--list-subparsers[=(<baselang>|all)]</span></code></dt><dd><p>Lists the subparsers for a base language for either the specified
<em><baselang></em> or <code class="docutils literal notranslate"><span class="pre">all</span></code> languages, and then exits.
<code class="docutils literal notranslate"><span class="pre">all</span></code> is used as default value if the option argument is omitted.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--machinable[=(yes|no)]</span></code></dt><dd><p>Use tab character as separators for <code class="docutils literal notranslate"><span class="pre">--list-</span></code> option output. It
may be suitable for scripting. See “<a class="reference internal" href="#list-options">List options</a>” for considered
use cases. Disabled by default.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--with-list-header[=(yes|no)]</span></code></dt><dd><p>Print headers describing columns in <code class="docutils literal notranslate"><span class="pre">--list-</span></code> option output.
See also “<a class="reference internal" href="#list-options">List options</a>”.</p>
</dd>
</dl>
</section>
<section id="miscellaneous-options">
<span id="option-misc"></span><h3>Miscellaneous Options<a class="headerlink" href="#miscellaneous-options" title="Permalink to this headline">¶</a></h3>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">--help</span></code></dt><dd><p>Prints to standard output a detailed usage description, and then exits.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-?</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--help</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--help-full</span></code></dt><dd><p>Prints to standard output a detailed usage description including experimental
features, and then exits. Visit <a class="reference external" href="https://docs.ctags.io/">https://docs.ctags.io/</a> for information
about the latest exciting experimental features.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--license</span></code></dt><dd><p>Prints a summary of the software license to standard output, and then exits.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--print-language</span></code></dt><dd><p>Just prints the language parsers for specified source files, and then exits.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--quiet[=(yes|no)]</span></code></dt><dd><p>Write fewer messages (default is <code class="docutils literal notranslate"><span class="pre">no</span></code>).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--totals[=(yes|no|extra)]</span></code></dt><dd><p>Prints statistics about the source files read and the tag file written
during the current invocation of ctags. This option
is <code class="docutils literal notranslate"><span class="pre">no</span></code> by default.</p>
<p>The <code class="docutils literal notranslate"><span class="pre">extra</span></code> value prints parser specific statistics for parsers
gathering such information.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--verbose[=(yes|no)]</span></code></dt><dd><p>Enable verbose mode. This prints out information on option processing
and a brief message describing what action is being taken for each file
considered by ctags. Normally, ctags
does not read command line arguments until after options are read
from the configuration files (see “<a class="reference internal" href="#files">FILES</a>”, below).
However, if this option is the first argument on
the command line, it will take effect before any options are read from
these sources. The default is <code class="docutils literal notranslate"><span class="pre">no</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-V</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--verbose</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--version</span></code></dt><dd><p>Prints a version identifier for ctags to standard
output, and then exits. This is guaranteed to always contain the string
“Universal Ctags”.</p>
</dd>
</dl>
</section>
<section id="obsoleted-options">
<h3>Obsoleted Options<a class="headerlink" href="#obsoleted-options" title="Permalink to this headline">¶</a></h3>
<p>These options are kept for backward-compatibility with Exuberant Ctags.</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">-w</span></code></dt><dd><p>This option is silently ignored for backward-compatibility with the
ctags of SVR4 Unix.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--file-scope[=(yes|no)]</span></code></dt><dd><p>This options is removed. Use <code class="docutils literal notranslate"><span class="pre">--extras=[+|-]F</span></code> or
<code class="docutils literal notranslate"><span class="pre">--extras=[+|-]{fileScope}</span></code> instead.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--extra=[+|-][<flags>|*]</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--extras=[+|-][<flags>|*]</span></code>, which was introduced to make
the option naming convention align to the other options like
<code class="docutils literal notranslate"><span class="pre">--kinds-<LANG>=</span></code> and <code class="docutils literal notranslate"><span class="pre">--fields=</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">--<LANG>-kinds=[+|-](<kinds>|*)</span></code></dt><dd><p>This option is obsolete. Use <code class="docutils literal notranslate"><span class="pre">--kinds-<LANG>=...</span></code> instead.</p>
</dd>
</dl>
</section>
</section>
<section id="operational-details">
<h2>OPERATIONAL DETAILS<a class="headerlink" href="#operational-details" title="Permalink to this headline">¶</a></h2>
<p>As ctags considers each source file name in turn, it tries to
determine the language of the file by applying tests described in
“<a class="reference internal" href="#determining-file-language">Determining file language</a>”.</p>
<p>If a language was identified, the file is opened and then the appropriate
language parser is called to operate on the currently open file. The parser
parses through the file and adds an entry to the tag file for each
language object it is written to handle. See “<a class="reference internal" href="#tag-file-format">TAG FILE FORMAT</a>”, below,
for details on these entries.</p>
<section id="notes-for-c-c-parser">
<h3>Notes for C/C++ Parser<a class="headerlink" href="#notes-for-c-c-parser" title="Permalink to this headline">¶</a></h3>
<p>This implementation of ctags imposes no formatting
requirements on C code as do legacy implementations. Older implementations
of ctags tended to rely upon certain formatting assumptions in order to
help it resolve coding dilemmas caused by preprocessor conditionals.</p>
<p>In general, ctags tries to be smart about conditional
preprocessor directives. If a preprocessor conditional is encountered
within a statement which defines a tag, ctags follows
only the first branch of that conditional (except in the special case of
<code class="docutils literal notranslate"><span class="pre">#if</span> <span class="pre">0</span></code>, in which case it follows only the last branch). The reason for
this is that failing to pursue only one branch can result in ambiguous
syntax, as in the following example:</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="cp">#ifdef TWO_ALTERNATIVES</span>
<span class="k">struct</span> <span class="p">{</span>
<span class="cp">#else</span>
<span class="k">union</span> <span class="p">{</span>
<span class="cp">#endif</span>
<span class="kt">short</span> <span class="n">a</span><span class="p">;</span>
<span class="kt">long</span> <span class="n">b</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Both branches cannot be followed, or braces become unbalanced and
ctags would be unable to make sense of the syntax.</p>
<p>If the application of this heuristic fails to properly parse a file,
generally due to complicated and inconsistent pairing within the
conditionals, ctags will retry the file using a
different heuristic which does not selectively follow conditional
preprocessor branches, but instead falls back to relying upon a closing
brace (’<code class="docutils literal notranslate"><span class="pre">}</span></code>’) in column 1 as indicating the end of a block once any brace
imbalance results from following a <code class="docutils literal notranslate"><span class="pre">#if</span></code> conditional branch.</p>
<p>ctags will also try to specially handle arguments lists
enclosed in double sets of parentheses in order to accept the following
conditional construct:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">extern</span> <span class="n">void</span> <span class="n">foo</span> <span class="n">__ARGS</span><span class="p">((</span><span class="nb">int</span> <span class="n">one</span><span class="p">,</span> <span class="n">char</span> <span class="n">two</span><span class="p">));</span>
</pre></div>
</div>
<p>Any name immediately preceding the ‘<code class="docutils literal notranslate"><span class="pre">((</span></code>’ will be automatically ignored and
the previous name will be used.</p>
<p>C++ operator definitions are specially handled. In order for consistency
with all types of operators (overloaded and conversion), the operator
name in the tag file will always be preceded by the string “operator ”
(i.e. even if the actual operator definition was written as “operator<<”).</p>
<p>After creating or appending to the tag file, it is sorted by the tag name,
removing identical tag lines.</p>
</section>
<section id="determining-file-language">
<span id="guessing"></span><h3>Determining file language<a class="headerlink" href="#determining-file-language" title="Permalink to this headline">¶</a></h3>
<section id="file-name-mapping">
<h4>File name mapping<a class="headerlink" href="#file-name-mapping" title="Permalink to this headline">¶</a></h4>
<p>Unless the <code class="docutils literal notranslate"><span class="pre">--language-force</span></code> option is specified, the language of each source
file is automatically selected based upon a <em>mapping</em> of file names to
languages. The mappings in effect for each language may be displayed using
the <code class="docutils literal notranslate"><span class="pre">--list-maps</span></code> option and may be changed using the <code class="docutils literal notranslate"><span class="pre">--langmap</span></code> or
<code class="docutils literal notranslate"><span class="pre">--map-<LANG></span></code> options.</p>
<p>If the name of a file is not mapped to a language, ctags tries
to heuristically guess the language for the file by inspecting its content.</p>
<p>All files that have no file name mapping and no guessed parser are
ignored. This permits running ctags on all files in
either a single directory (e.g. “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">*</span></code>”), or on
all files in an entire source directory tree
(e.g. “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">-R</span></code>”), since only those files whose
names are mapped to languages will be scanned.</p>
<p>An extension may be mapped to multiple parsers. For example, <code class="docutils literal notranslate"><span class="pre">.h</span></code>
are mapped to C++, C and ObjectiveC. These mappings can cause
issues. ctags tries to select the proper parser
for the source file by applying heuristics to its content, however
it is not perfect. In case of issues one can use <code class="docutils literal notranslate"><span class="pre">--language-force=<language></span></code>,
<code class="docutils literal notranslate"><span class="pre">--langmap=<map>[,<map>[...]]</span></code>, or the <code class="docutils literal notranslate"><span class="pre">--map-<LANG>=[+|-]<extension>|<pattern></span></code>
options. (Some of the heuristics are applied whether <code class="docutils literal notranslate"><span class="pre">--guess-language-eagerly</span></code>
is given or not.)</p>
</section>
<section id="heuristically-guessing">
<h4>Heuristically guessing<a class="headerlink" href="#heuristically-guessing" title="Permalink to this headline">¶</a></h4>
<p>If ctags cannot select a parser from the mapping of file names,
various heuristic tests are conducted to determine the language:</p>
<dl>
<dt>template file name testing</dt><dd><p>If the file name has an <code class="docutils literal notranslate"><span class="pre">.in</span></code> extension, ctags applies
the mapping to the file name without the extension. For example,
<code class="docutils literal notranslate"><span class="pre">config.h</span></code> is tested for a file named <code class="docutils literal notranslate"><span class="pre">config.h.in</span></code>.</p>
</dd>
<dt>“interpreter” testing</dt><dd><p>The first line of the file is checked to see if the file is a <code class="docutils literal notranslate"><span class="pre">#!</span></code>
script for a recognized language. ctags looks for
a parser having the same name.</p>
<p>If ctags finds no such parser,
ctags looks for the name in alias lists. For
example, consider if the first line is <code class="docutils literal notranslate"><span class="pre">#!/bin/sh</span></code>. Though
ctags has a “shell” parser, it doesn’t have a “sh”
parser. However, <code class="docutils literal notranslate"><span class="pre">sh</span></code> is listed as an alias for <code class="docutils literal notranslate"><span class="pre">shell</span></code>, therefore
ctags selects the “shell” parser for the file.</p>
<p>An exception is <code class="docutils literal notranslate"><span class="pre">env</span></code>. If <code class="docutils literal notranslate"><span class="pre">env</span></code> is specified (for example
“<code class="docutils literal notranslate"><span class="pre">#!/usr/bin/env</span> <span class="pre">python</span></code>”), ctags
reads more lines to find real interpreter specification.</p>
<p>To display the list of aliases, use <code class="docutils literal notranslate"><span class="pre">--list-aliases</span></code> option.
To add an item to the list or to remove an item from the list, use the
<code class="docutils literal notranslate"><span class="pre">--alias-<LANG>=+<pattern></span></code> or <code class="docutils literal notranslate"><span class="pre">--alias-<LANG>=-<pattern></span></code> option
respectively.</p>
</dd>
<dt>“zsh autoload tag” testing</dt><dd><p>If the first line starts with <code class="docutils literal notranslate"><span class="pre">#compdef</span></code> or <code class="docutils literal notranslate"><span class="pre">#autoload</span></code>,
ctags regards the line as “zsh”.</p>
</dd>
<dt>“emacs mode at the first line” testing</dt><dd><p>The Emacs editor has multiple editing modes specialized for programming
languages. Emacs can recognize a marker called modeline in a file
and utilize the marker for the mode selection. This heuristic test does
the same as what Emacs does.</p>
<p>ctags treats <code class="docutils literal notranslate"><span class="pre">MODE</span></code> as a name of interpreter and applies the same
rule of “interpreter” testing if the first line has one of
the following patterns:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="o">-*-</span> <span class="n">mode</span><span class="p">:</span> <span class="n">MODE</span> <span class="o">-*-</span>
</pre></div>
</div>
<p>or</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="o">-*-</span> <span class="n">MODE</span> <span class="o">-*-</span>
</pre></div>
</div>
</dd>
<dt>“emacs mode at the EOF” testing</dt><dd><p>Emacs editor recognizes another marker at the end of file as a
mode specifier. This heuristic test does the same as what Emacs does.</p>
<p>ctags treats <code class="docutils literal notranslate"><span class="pre">MODE</span></code> as a name of an interpreter and applies the same
rule of “interpreter” heuristic testing, if the lines at the tail of the file
have the following pattern:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">Local</span> <span class="n">Variables</span><span class="p">:</span>
<span class="o">...</span>
<span class="n">mode</span><span class="p">:</span> <span class="n">MODE</span>
<span class="o">...</span>
<span class="n">End</span><span class="p">:</span>
</pre></div>
</div>
<p>3000 characters are sought from the end of file to find the pattern.</p>
</dd>
<dt>“vim modeline” testing</dt><dd><p>Like the modeline of the Emacs editor, Vim editor has the same concept.
ctags treats <code class="docutils literal notranslate"><span class="pre">TYPE</span></code> as a name of interpreter and applies the same
rule of “interpreter” heuristic testing if the last 5 lines of the file
have one of the following patterns:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">filetype</span><span class="o">=</span><span class="n">TYPE</span>
</pre></div>
</div>
<p>or</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">ft</span><span class="o">=</span><span class="n">TYPE</span>
</pre></div>
</div>
</dd>
<dt>“PHP marker” testing</dt><dd><p>If the first line is started with <code class="docutils literal notranslate"><span class="pre"><?php</span></code>,
ctags regards the line as “php”.</p>
</dd>
</dl>
<p>Looking into the file contents is a more expensive operation than file
name matching. So ctags runs the testings in limited
conditions. “interpreter” testing is enabled only when a file is an
executable or the <code class="docutils literal notranslate"><span class="pre">--guess-language-eagerly</span></code> (<code class="docutils literal notranslate"><span class="pre">-G</span></code> in short) option is
given. The other heuristic tests are enabled only when <code class="docutils literal notranslate"><span class="pre">-G</span></code> option is
given.</p>
<p>The <code class="docutils literal notranslate"><span class="pre">--print-language</span></code> option can be used just to print the results of
parser selections for given files instead of generating a tags file.</p>
<p>Examples:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --print-language config.h.in input.m input.unknown
<span class="go">config.h.in: C++</span>
<span class="go">input.m: MatLab</span>
<span class="go">input.unknown: NONE</span>
</pre></div>
</div>
<p><code class="docutils literal notranslate"><span class="pre">NONE</span></code> means that ctags does not select any parser for the file.</p>
</section>
</section>
</section>
<section id="tag-file-format">
<h2>TAG FILE FORMAT<a class="headerlink" href="#tag-file-format" title="Permalink to this headline">¶</a></h2>
<p>This section describes the tag file format briefly. See <a class="reference internal" href="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a> and
<a class="reference internal" href="ctags-client-tools.7.html#ctags-client-tools-7"><span class="std std-ref">ctags-client-tools(7)</span></a> for more details.</p>
<p>When not running in etags mode, each entry in the tag file consists of a
separate line, each looking like this, called <em>regular tags</em>, in the most general case:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="o"><</span><span class="n">tag_name</span><span class="o">><</span><span class="n">TAB</span><span class="o">><</span><span class="n">file_name</span><span class="o">><</span><span class="n">TAB</span><span class="o">><</span><span class="n">ex_cmd</span><span class="o">></span><span class="p">;</span><span class="s2">"<TAB><extension_fields></span>
</pre></div>
</div>
<p>The fields and separators of these lines are specified as follows:</p>
<blockquote>
<div><ol class="arabic">
<li><p><code class="docutils literal notranslate"><span class="pre"><tag_name></span></code>: tag name</p></li>
<li><p><code class="docutils literal notranslate"><span class="pre"><TAB></span></code>: single tab character</p></li>
<li><p><code class="docutils literal notranslate"><span class="pre"><file_name></span></code>: name of the file in which the object associated with the tag is located</p></li>
<li><p><code class="docutils literal notranslate"><span class="pre"><TAB></span></code>: single tab character</p></li>
<li><p><code class="docutils literal notranslate"><span class="pre"><ex_cmd></span></code>: EX command used to locate the tag within the file; generally a
search pattern (either <code class="docutils literal notranslate"><span class="pre">/pattern/</span></code> or <code class="docutils literal notranslate"><span class="pre">?pattern?</span></code>) or line number (see
<code class="docutils literal notranslate"><span class="pre">--excmd=<type></span></code> option).</p></li>
<li><p><code class="docutils literal notranslate"><span class="pre">;"<TAB><extension_fields></span></code>: a set of extension fields. See
“<a class="reference internal" href="#extension-fields">Extension fields</a>” for more details.</p>
<p>Tag file format 2 (see <code class="docutils literal notranslate"><span class="pre">--format</span></code>) extends the EX command
to include the extension fields embedded in an EX comment immediately appended
to the EX command, which leaves it backward-compatible with original
<code class="docutils literal notranslate"><span class="pre">vi(1)</span></code> implementations.</p>
</li>
</ol>
</div></blockquote>
<p>A few special tags, called <em>pseudo tags</em>, are written into the tag file for internal purposes.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span>!_TAG_FILE_FORMAT 2 /extended format; --format=1 will not append ;" to lines/
!_TAG_FILE_SORTED 1 /0=unsorted, 1=sorted, 2=foldcase/
...
</pre></div>
</div>
<p><code class="docutils literal notranslate"><span class="pre">--pseudo-tags=[+|-](<pseudo-tag>|*)</span></code> option enables or disables emitting pseudo-tags.</p>
<p>See the output of “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">--list-pseudo-tags</span></code>” for the list of
the kinds.
See also <a class="reference internal" href="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a> and <a class="reference internal" href="ctags-client-tools.7.html#ctags-client-tools-7"><span class="std std-ref">ctags-client-tools(7)</span></a> for more details of the pseudo tags.</p>
<p>These tags are composed in such a way that they always sort to the top of
the file. Therefore, the first two characters of these tags are used a magic
number to detect a tag file for purposes of determining whether a
valid tag file is being overwritten rather than a source file.</p>
<p>Note that the name of each source file will be recorded in the tag file
exactly as it appears on the command line. Therefore, if the path you
specified on the command line was relative to the current directory, then
it will be recorded in that same manner in the tag file. See, however,
the <code class="docutils literal notranslate"><span class="pre">--tag-relative=(yes|no|always|never)</span></code> option for how this behavior can be
modified.</p>
</section>
<section id="tag-entries">
<span id="id1"></span><h2>TAG ENTRIES<a class="headerlink" href="#tag-entries" title="Permalink to this headline">¶</a></h2>
<p>A tag is an index for a language object. The concept of a tag and related
items in Exuberant Ctags are refined and extended in Universal Ctags.</p>
<p>A tag is categorized into <em>definition tags</em> or <em>reference tags</em>.
In general, Exuberant Ctags only tags <em>definitions</em> of
language objects: places where newly named language objects <em>are introduced</em>.
Universal Ctags, on the other hand, can also tag <em>references</em> of language
objects: places where named language objects <em>are used</em>. However, support
for generating reference tags is new and limited to specific areas of
specific languages in the current version.</p>
<section id="extension-fields">
<h3>Extension fields<a class="headerlink" href="#extension-fields" title="Permalink to this headline">¶</a></h3>
<p>A tag can record various information, called <em>extension fields</em>.</p>
<p>Extension fields are tab-separated key-value pairs appended to the end of
the EX command as a comment, as described above. These key value pairs
appear in the general form <code class="docutils literal notranslate"><span class="pre">key:value</span></code>.</p>
<p>In addition, information on the scope of the tag definition may be
available, with the key portion equal to some language-dependent construct
name and its value the name declared for that construct in the program.
This scope entry indicates the scope in which the tag was found.
For example, a tag generated for a C structure member would have a scope
looking like <code class="docutils literal notranslate"><span class="pre">struct:myStruct</span></code>.</p>
<p><code class="docutils literal notranslate"><span class="pre">--fields=[+|-][<flags>|*]</span></code> and <code class="docutils literal notranslate"><span class="pre">--fields-(<LANG>|all)=[+|-][<flags>|*]</span></code> options specifies
which available extension fields are to be included in the tag entries.</p>
<p>See the output of “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">--list-fields</span></code>” for the list of
extension fields.
The essential fields are <code class="docutils literal notranslate"><span class="pre">name</span></code>, <code class="docutils literal notranslate"><span class="pre">input</span></code>, <code class="docutils literal notranslate"><span class="pre">pattern</span></code>, and <code class="docutils literal notranslate"><span class="pre">line</span></code>.
The meaning of major fields is as follows (long-name flag/one-letter flag):</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">access</span></code>/<code class="docutils literal notranslate"><span class="pre">a</span></code></dt><dd><p>Indicates the visibility of this class member, where value is specific
to the language.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">end</span></code>/<code class="docutils literal notranslate"><span class="pre">e</span></code></dt><dd><p>Indicates the line number of the end lines of the language object.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">extras</span></code>/<code class="docutils literal notranslate"><span class="pre">E</span></code></dt><dd><p>Extra tag type information. See “<a class="reference internal" href="#extras">Extras</a>” for details.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">file</span></code>/<code class="docutils literal notranslate"><span class="pre">f</span></code></dt><dd><p>Indicates that the tag has file-limited visibility. This key has no
corresponding value. Enabled by default.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">implementation</span></code>/<code class="docutils literal notranslate"><span class="pre">m</span></code></dt><dd><p>When present, this indicates a limited implementation (abstract vs.
concrete) of a routine or class, where value is specific to the
language (<code class="docutils literal notranslate"><span class="pre">virtual</span></code> or <code class="docutils literal notranslate"><span class="pre">pure</span> <span class="pre">virtual</span></code> for C++; <code class="docutils literal notranslate"><span class="pre">abstract</span></code> for Java).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">inherits</span></code>/<code class="docutils literal notranslate"><span class="pre">i</span></code></dt><dd><p>When present, value is a comma-separated list of classes from which
this class is derived (i.e. inherits from).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">input</span></code>/<code class="docutils literal notranslate"><span class="pre">F</span></code></dt><dd><p>The name of source file where <code class="docutils literal notranslate"><span class="pre">name</span></code> is defined or referenced.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">k</span></code></dt><dd><p><a class="reference external" href="Kinds">Kind</a> of tag as one-letter. Enabled by default.
This field has no long-name.
See also <code class="docutils literal notranslate"><span class="pre">kind</span></code>/<code class="docutils literal notranslate"><span class="pre">z</span></code> flag.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">K</span></code></dt><dd><p><a class="reference external" href="Kinds">Kind</a> of tag as long-name.
This field has no long-name.
See also <code class="docutils literal notranslate"><span class="pre">kind</span></code>/<code class="docutils literal notranslate"><span class="pre">z</span></code> flag.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">kind</span></code>/<code class="docutils literal notranslate"><span class="pre">z</span></code></dt><dd><p>Include the <code class="docutils literal notranslate"><span class="pre">kind:</span></code> key in <a class="reference external" href="Kinds">kind field</a>. See also <code class="docutils literal notranslate"><span class="pre">k</span></code> and <code class="docutils literal notranslate"><span class="pre">K</span></code> flags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">language</span></code>/<code class="docutils literal notranslate"><span class="pre">l</span></code></dt><dd><p>Language of source file containing tag</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">line</span></code>/<code class="docutils literal notranslate"><span class="pre">n</span></code></dt><dd><p>The line number where <code class="docutils literal notranslate"><span class="pre">name</span></code> is defined or referenced in <code class="docutils literal notranslate"><span class="pre">input</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">name</span></code>/<code class="docutils literal notranslate"><span class="pre">N</span></code></dt><dd><p>The name of language objects.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">pattern</span></code>/<code class="docutils literal notranslate"><span class="pre">P</span></code></dt><dd><p>Can be used to search the <code class="docutils literal notranslate"><span class="pre">name</span></code> in <code class="docutils literal notranslate"><span class="pre">input</span></code></p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">roles</span></code>/<code class="docutils literal notranslate"><span class="pre">r</span></code></dt><dd><p>Roles assigned to the tag. See “<a class="reference internal" href="#roles">Roles</a>” for more details.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">s</span></code></dt><dd><p>Scope of tag definition. Enabled by default.
This field has no long-name.
See also <code class="docutils literal notranslate"><span class="pre">scope</span></code>/<code class="docutils literal notranslate"><span class="pre">Z</span></code> flag.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">scope</span></code>/<code class="docutils literal notranslate"><span class="pre">Z</span></code></dt><dd><p>Prepend the <code class="docutils literal notranslate"><span class="pre">scope:</span></code> key to scope (<code class="docutils literal notranslate"><span class="pre">s</span></code>) field.
See also <code class="docutils literal notranslate"><span class="pre">s</span></code> flag.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">scopeKind</span></code>/<code class="docutils literal notranslate"><span class="pre">p</span></code></dt><dd><p>Kind of scope as long-name</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">signature</span></code>/<code class="docutils literal notranslate"><span class="pre">S</span></code></dt><dd><p>When present, value is a language-dependent representation of the
signature of a routine (e.g. prototype or parameter list). A routine signature in its complete form
specifies the return type of a routine and its formal argument list.
This extension field is presently supported only for C-based
languages and does not include the return type.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">typeref</span></code>/<code class="docutils literal notranslate"><span class="pre">t</span></code></dt><dd><p>Type and name of a variable, typedef, or return type of
callable like function as <code class="docutils literal notranslate"><span class="pre">typeref:</span></code> field.
Enabled by default.</p>
</dd>
</dl>
<section id="kinds">
<h4>Kinds<a class="headerlink" href="#kinds" title="Permalink to this headline">¶</a></h4>
<p><code class="docutils literal notranslate"><span class="pre">kind</span></code> is a field which represents the <em>kind</em> of language object
specified by a tag. Kinds used and defined are very different between
parsers. For example, C language defines <code class="docutils literal notranslate"><span class="pre">macro</span></code>, <code class="docutils literal notranslate"><span class="pre">function</span></code>,
<code class="docutils literal notranslate"><span class="pre">variable</span></code>, <code class="docutils literal notranslate"><span class="pre">typedef</span></code>, etc.</p>
<p><code class="docutils literal notranslate"><span class="pre">--kinds-(<LANG>|all)=[+|-](<kinds>|*)</span></code> option specifies a list of language-specific
kinds of tags (or kinds) to include in the output file for a particular
language.</p>
<p>See the output of “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">--list-kinds-full</span></code>” for the complete
list of the kinds.</p>
<p>Its value is either one of the
corresponding one-letter flags or a long-name flag. It is permitted
(and is, in fact, the default) for the key portion of this field to be
omitted. The optional behaviors are controlled with the <code class="docutils literal notranslate"><span class="pre">--fields</span></code> option as follows.</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags -o - kinds.c
<span class="go">foo kinds.c /^int foo() {$/;" f typeref:typename:int</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+k -o - kinds.c
<span class="go">foo kinds.c /^int foo() {$/;" f typeref:typename:int</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+K -o - kinds.c
<span class="go">foo kinds.c /^int foo() {$/;" function typeref:typename:int</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+z -o - kinds.c
<span class="go">foo kinds.c /^int foo() {$/;" kind:f typeref:typename:int</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+zK -o - kinds.c
<span class="go">foo kinds.c /^int foo() {$/;" kind:function typeref:typename:int</span>
</pre></div>
</div>
</section>
<section id="roles">
<h4>Roles<a class="headerlink" href="#roles" title="Permalink to this headline">¶</a></h4>
<p><em>Role</em> is a newly introduced concept in Universal Ctags. Role is a
concept associated with reference tags, and is not implemented widely yet.</p>
<p>As described previously in “<a class="reference internal" href="#kinds">Kinds</a>”, the <code class="docutils literal notranslate"><span class="pre">kind</span></code> field represents the type
of language object specified with a tag, such as a function vs. a variable.
Specific kinds are defined for reference tags, such as the C++ kind <code class="docutils literal notranslate"><span class="pre">header</span></code> for
header file, or Java kind <code class="docutils literal notranslate"><span class="pre">package</span></code> for package statements. For such reference
kinds, a <code class="docutils literal notranslate"><span class="pre">roles</span></code> field can be added to distinguish the role of the reference
kind. In other words, the <code class="docutils literal notranslate"><span class="pre">kind</span></code> field identifies the <em>what</em> of the language
object, whereas the <code class="docutils literal notranslate"><span class="pre">roles</span></code> field identifies the <em>how</em> of a referenced language
object. Roles are only used with specific kinds.</p>
<p>For a definition tag, this field takes <code class="docutils literal notranslate"><span class="pre">def</span></code> as a value.</p>
<p>For example, <code class="docutils literal notranslate"><span class="pre">Baz</span></code> is tagged as a reference tag with kind <code class="docutils literal notranslate"><span class="pre">package</span></code> and with
role <code class="docutils literal notranslate"><span class="pre">imported</span></code> with the following code.</p>
<div class="highlight-java notranslate"><div class="highlight"><pre><span></span><span class="kn">package</span> <span class="nn">Bar</span><span class="p">;</span>
<span class="kn">import</span> <span class="nn">Baz</span><span class="p">;</span>
<span class="kd">class</span> <span class="nc">Foo</span> <span class="p">{</span>
<span class="c1">// ...</span>
<span class="p">}</span>
</pre></div>
</div>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --fields<span class="o">=</span>+KEr -uo - roles.java
<span class="go">Bar roles.java /^package Bar;$/;" package roles:def</span>
<span class="go">Foo roles.java /^class Foo {$/;" class roles:def</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+EKr --extras<span class="o">=</span>+r -uo - roles.java
<span class="go">Bar roles.java /^package Bar;$/;" package roles:def</span>
<span class="go">Baz roles.java /^import Baz;$/;" package roles:imported extras:reference</span>
<span class="go">Foo roles.java /^class Foo {$/;" class roles:def</span>
</pre></div>
</div>
<p><code class="docutils literal notranslate"><span class="pre">--roles-(<LANG>|all).(<kind>|all)=[+|-][<roles>|*]</span></code> option specifies a list of kind-specific
roles of tags to include in the output file for a particular language.</p>
<p>Inquire the output of “<code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">--list-roles</span></code>” for the list of
roles.</p>
</section>
</section>
<section id="extras">
<h3>Extras<a class="headerlink" href="#extras" title="Permalink to this headline">¶</a></h3>
<p>Generally, ctags tags only language objects appearing
in source files, as is. In other words, a value for a <code class="docutils literal notranslate"><span class="pre">name:</span></code> field
should be found on the source file associated with the <code class="docutils literal notranslate"><span class="pre">name:</span></code>. An
<code class="docutils literal notranslate"><span class="pre">extra</span></code> type tag (<em>extra</em>) is for tagging a language object with a processed
name, or for tagging something not associated with a language object. A typical
extra tag is <code class="docutils literal notranslate"><span class="pre">qualified</span></code>, which tags a language object with a
class-qualified or scope-qualified name.</p>
<p><code class="docutils literal notranslate"><span class="pre">--extras-(<LANG>|all)=[+|-][<flags>|*]</span></code> option specifies
whether to include extra tag entries for certain kinds of information.</p>
<p>Inquire the output of <code class="docutils literal notranslate"><span class="pre">ctags</span> <span class="pre">--list-extras</span></code> for the list of extras.
The meaning of major extras is as follows (long-name flag/one-letter flag):</p>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">anonymous</span></code>/none</dt><dd><p>Include an entry for the language object that has no name like lambda
function. This extra has no one-letter flag and is enabled by
default.</p>
<p>The extra tag is useful as a placeholder to fill scope fields
for language objects defined in a language object with no name.</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="k">struct</span> <span class="p">{</span>
<span class="kt">double</span> <span class="n">x</span><span class="p">,</span> <span class="n">y</span><span class="p">;</span>
<span class="p">}</span> <span class="n">p</span> <span class="o">=</span> <span class="p">{</span> <span class="p">.</span><span class="n">x</span> <span class="o">=</span> <span class="mf">0.0</span><span class="p">,</span> <span class="p">.</span><span class="n">y</span> <span class="o">=</span> <span class="mf">0.0</span> <span class="p">};</span>
</pre></div>
</div>
<p>‘<code class="docutils literal notranslate"><span class="pre">x</span></code>’ and ‘<code class="docutils literal notranslate"><span class="pre">y</span></code>’ are the members of a structure. When filling the scope
fields for them, ctags has trouble because the struct
where ‘<code class="docutils literal notranslate"><span class="pre">x</span></code>’ and ‘<code class="docutils literal notranslate"><span class="pre">y</span></code>’ belong to has no name. For overcoming the trouble,
ctags generates an anonymous extra tag for the struct
and fills the scope fields with the name of the extra tag.</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --fields<span class="o">=</span>-f -uo - input.c
<span class="go">__anon9f26d2460108 input.c /^struct {$/;" s</span>
<span class="go">x input.c /^ double x, y;$/;" m struct:__anon9f26d2460108</span>
<span class="go">y input.c /^ double x, y;$/;" m struct:__anon9f26d2460108</span>
<span class="go">p input.c /^} p = { .x = 0.0, .y = 0.0 };$/;" v typeref:struct:__anon9f26d2460108</span>
</pre></div>
</div>
<p>The above tag output has <code class="docutils literal notranslate"><span class="pre">__anon9f26d2460108</span></code> as an anonymous extra tag.
The typeref field of ‘<code class="docutils literal notranslate"><span class="pre">p</span></code>’ also receives the benefit of it.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">fileScope</span></code>/<code class="docutils literal notranslate"><span class="pre">F</span></code></dt><dd><p>Indicates whether tags scoped only for a single file (i.e. tags which
cannot be seen outside of the file in which they are defined, such as
language objects with <code class="docutils literal notranslate"><span class="pre">static</span></code> modifier of C language) should be included
in the output. See also the <code class="docutils literal notranslate"><span class="pre">-h</span></code> option.</p>
<p>This extra tag is enabled by default. Add <code class="docutils literal notranslate"><span class="pre">--extras=-F</span></code> option not to
output tags scoped only for a single-file. This is the replacement for
<code class="docutils literal notranslate"><span class="pre">--file-scope</span></code> option of Exuberant Ctags.</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="k">static</span> <span class="kt">int</span> <span class="nf">f</span><span class="p">()</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="kt">int</span> <span class="nf">g</span><span class="p">()</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags -uo - filescope.c
<span class="go">f filescope.c /^static int f() {$/;" f typeref:typename:int file:</span>
<span class="go">g filescope.c /^int g() {$/;" f typeref:typename:int</span>
<span class="gp">$ </span>ctags --extras<span class="o">=</span>-F -uo - filescope.c
<span class="go">g filescope.c /^int g() {$/;" f typeref:typename:int</span>
</pre></div>
</div>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">inputFile</span></code>/<code class="docutils literal notranslate"><span class="pre">f</span></code></dt><dd><p>Include an entry for the base file name of every source file
(e.g. <code class="docutils literal notranslate"><span class="pre">example.c</span></code>), which addresses the first line of the file.
This flag is the replacement for <code class="docutils literal notranslate"><span class="pre">--file-tags</span></code> hidden option of
Exuberant Ctags.</p>
<p>If the <code class="docutils literal notranslate"><span class="pre">end:</span></code> field is enabled, the end line number of the file can be
attached to the tag. (However, ctags omits the <code class="docutils literal notranslate"><span class="pre">end:</span></code> field
if no newline is in the file like an empty file.)</p>
<p>By default, ctags doesn’t create the <code class="docutils literal notranslate"><span class="pre">inputFile</span></code>/<code class="docutils literal notranslate"><span class="pre">f</span></code> extra
tag for the source file when ctags doesn’t find a parser
for it. Enabling <code class="docutils literal notranslate"><span class="pre">Unknown</span></code> parser with <code class="docutils literal notranslate"><span class="pre">--languages=+Unknown</span></code> forces
ctags to create the extra tags for any source files.</p>
<p>The etags mode enables the <code class="docutils literal notranslate"><span class="pre">Unknown</span></code> parser implicitly.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">pseudo</span></code>/<code class="docutils literal notranslate"><span class="pre">p</span></code></dt><dd><p>Include pseudo-tags. Enabled by default unless the tag file is
written to standard output. See <a class="reference internal" href="ctags-client-tools.7.html#ctags-client-tools-7"><span class="std std-ref">ctags-client-tools(7)</span></a> about
the detail of pseudo-tags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">qualified</span></code>/<code class="docutils literal notranslate"><span class="pre">q</span></code></dt><dd><p>Include an extra class-qualified or namespace-qualified tag entry
for each tag which is a member of a class or a namespace.</p>
<p>This may allow easier location of a specific tags when
multiple occurrences of a tag name occur in the tag file.
Note, however, that this could potentially more than double
the size of the tag file.</p>
<p>The actual form of the qualified tag depends upon the language
from which the tag was derived (using a form that is most
natural for how qualified calls are specified in the
language). For C++ and Perl, it is in the form
<code class="docutils literal notranslate"><span class="pre">class::member</span></code>; for Eiffel and Java, it is in the form
<code class="docutils literal notranslate"><span class="pre">class.member</span></code>.</p>
<p>Note: Using backslash characters as separators forming
qualified name in PHP. However, in tags output of
Universal Ctags, a backslash character in a name is escaped
with a backslash character. See <a class="reference internal" href="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a> about the escaping.</p>
<p>The following example demonstrates the <code class="docutils literal notranslate"><span class="pre">qualified</span></code> extra tag.</p>
<div class="highlight-Java notranslate"><div class="highlight"><pre><span></span><span class="kd">class</span> <span class="nc">point</span> <span class="p">{</span>
<span class="kt">double</span> <span class="n">x</span><span class="p">;</span>
<span class="p">};</span>
</pre></div>
</div>
<p>For the above source file, ctags tags <code class="docutils literal notranslate"><span class="pre">point</span></code> and <code class="docutils literal notranslate"><span class="pre">x</span></code> by
default. If the <code class="docutils literal notranslate"><span class="pre">qualified</span></code> extra is enabled from the command line
(<code class="docutils literal notranslate"><span class="pre">--extras=+q</span></code>), then <code class="docutils literal notranslate"><span class="pre">point.x</span></code> is also tagged even though the string
“<code class="docutils literal notranslate"><span class="pre">point.x</span></code>” is not in the source code.</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --fields<span class="o">=</span>+K -uo - qualified.java
<span class="go">point qualified.java /^class point {$/;" class</span>
<span class="go">x qualified.java /^ double x;$/;" field class:point</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+K --extras<span class="o">=</span>+q -uo - qualified.java
<span class="go">point qualified.java /^class point {$/;" class</span>
<span class="go">x qualified.java /^ double x;$/;" field class:point</span>
<span class="go">point.x qualified.java /^ double x;$/;" field class:point</span>
</pre></div>
</div>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">reference</span></code>/<code class="docutils literal notranslate"><span class="pre">r</span></code></dt><dd><p>Include reference tags. See “<a class="reference internal" href="#id1">TAG ENTRIES</a>” about reference tags.</p>
<p>The following example demonstrates the <code class="docutils literal notranslate"><span class="pre">reference</span></code> extra tag.</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="cp">#include</span> <span class="cpf"><stdio.h></span><span class="cp"></span>
<span class="cp">#include</span> <span class="cpf">"utils.h"</span><span class="cp"></span>
<span class="cp">#define X</span>
<span class="cp">#undef X</span>
</pre></div>
</div>
<p>The <code class="docutils literal notranslate"><span class="pre">roles:system</span></code> or <code class="docutils literal notranslate"><span class="pre">roles:local</span></code> fields will be
added depending on whether the include file name begins with ‘<code class="docutils literal notranslate"><span class="pre"><</span></code>’ or not.</p>
<p>“<code class="docutils literal notranslate"><span class="pre">#define</span> <span class="pre">X</span></code>” emits a definition tag. On the other hand “<code class="docutils literal notranslate"><span class="pre">#undef</span> <span class="pre">X</span></code>” emits a
reference tag.</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>ctags --fields<span class="o">=</span>+EKr -uo - inc.c
<span class="go">X inc.c /^#define X$/;" macro file: roles:def extras:fileScope</span>
<span class="gp">$ </span>ctags --fields<span class="o">=</span>+EKr --extras<span class="o">=</span>+r -uo - inc.c
<span class="go">stdio.h inc.c /^#include <stdio.h>/;" header roles:system extras:reference</span>
<span class="go">utils.h inc.c /^#include "utils.h"/;" header roles:local extras:reference</span>
<span class="go">X inc.c /^#define X$/;" macro file: roles:def extras:fileScope</span>
<span class="go">X inc.c /^#undef X$/;" macro file: roles:undef extras:fileScope,reference</span>
</pre></div>
</div>
</dd>
</dl>
</section>
<section id="language-specific-fields-and-extras">
<h3>Language-specific fields and extras<a class="headerlink" href="#language-specific-fields-and-extras" title="Permalink to this headline">¶</a></h3>
<p>Exuberant Ctags has the concept of <em>fields</em> and <em>extras</em>. They are common
between parsers of different languages. Universal Ctags extends this concept
by providing language-specific fields and extras.</p>
</section>
</section>
<section id="how-to-use-with-vi">
<h2>HOW TO USE WITH VI<a class="headerlink" href="#how-to-use-with-vi" title="Permalink to this headline">¶</a></h2>
<p><code class="docutils literal notranslate"><span class="pre">vi(1)</span></code> will, by default, expect a tag file by the name <code class="docutils literal notranslate"><span class="pre">tags</span></code> in the current
directory. Once the tag file is built, the following commands exercise
the tag indexing feature:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">vi</span> <span class="pre">-t</span> <span class="pre">tag</span></code></dt><dd><p>Start vi and position the cursor at the file and line where <code class="docutils literal notranslate"><span class="pre">tag</span></code>
is defined.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">:ta</span> <span class="pre">tag</span></code></dt><dd><p>Find a tag.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">Ctrl-]</span></code></dt><dd><p>Find the tag under the cursor.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">Ctrl-T</span></code></dt><dd><p>Return to previous location before jump to tag (not widely implemented).</p>
</dd>
</dl>
</section>
<section id="how-to-use-with-gnu-emacs">
<h2>HOW TO USE WITH GNU EMACS<a class="headerlink" href="#how-to-use-with-gnu-emacs" title="Permalink to this headline">¶</a></h2>
<p><code class="docutils literal notranslate"><span class="pre">emacs(1)</span></code> will, by default, expect a tag file by the name <code class="docutils literal notranslate"><span class="pre">TAGS</span></code> in the
current directory. Once the tag file is built, the following commands
exercise the tag indexing feature:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">M-x</span> <span class="pre">visit-tags-table</span> <span class="pre"><RET></span> <span class="pre">FILE</span> <span class="pre"><RET></span></code></dt><dd><p>Select the tag file, <code class="docutils literal notranslate"><span class="pre">FILE</span></code>, to use.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">M-.</span> <span class="pre">[TAG]</span> <span class="pre"><RET></span></code></dt><dd><p>Find the first definition of TAG. The default tag is the identifier
under the cursor.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">M-*</span></code></dt><dd><p>Pop back to where you previously invoked <code class="docutils literal notranslate"><span class="pre">M-.</span></code>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">C-u</span> <span class="pre">M-.</span></code></dt><dd><p>Find the next definition for the last tag.</p>
</dd>
</dl>
<p>For more commands, see the Tags topic in the Emacs info document.</p>
</section>
<section id="how-to-use-with-nedit">
<h2>HOW TO USE WITH NEDIT<a class="headerlink" href="#how-to-use-with-nedit" title="Permalink to this headline">¶</a></h2>
<p>NEdit version 5.1 and later can handle the new extended tag file format
(see <code class="docutils literal notranslate"><span class="pre">--format</span></code>).</p>
<ul class="simple">
<li><p>To make NEdit use the tag file, select “File->Load Tags File”.</p></li>
<li><p>To jump to the definition for a tag, highlight the word, then press <code class="docutils literal notranslate"><span class="pre">Ctrl-D</span></code>.</p></li>
</ul>
<p>NEdit 5.1 can read multiple tag files from different
directories. Setting the X resource <code class="docutils literal notranslate"><span class="pre">nedit.tagFile</span></code> to the name of a tag
file instructs NEdit to automatically load that tag file at startup time.</p>
</section>
<section id="caveats">
<h2>CAVEATS<a class="headerlink" href="#caveats" title="Permalink to this headline">¶</a></h2>
<p>Because ctags is neither a preprocessor nor a compiler,
use of preprocessor macros can fool ctags into either
missing tags or improperly generating inappropriate tags. Although
ctags has been designed to handle certain common cases,
this is the single biggest cause of reported problems. In particular,
the use of preprocessor constructs which alter the textual syntax of C
can fool ctags. You can work around many such problems
by using the <code class="docutils literal notranslate"><span class="pre">-I</span></code> option.</p>
<p>Note that since ctags generates patterns for locating
tags (see the <code class="docutils literal notranslate"><span class="pre">--excmd</span></code> option), it is entirely possible that the wrong line
may be found by your editor if there exists another source line which is
identical to the line containing the tag. The following example
demonstrates this condition:</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="kt">int</span> <span class="n">variable</span><span class="p">;</span>
<span class="cm">/* ... */</span>
<span class="kt">void</span> <span class="nf">foo</span><span class="p">(</span><span class="n">variable</span><span class="p">)</span>
<span class="kt">int</span> <span class="n">variable</span><span class="p">;</span>
<span class="p">{</span>
<span class="cm">/* ... */</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Depending upon which editor you use and where in the code you happen to be,
it is possible that the search pattern may locate the local parameter
declaration before it finds the actual global variable definition,
since the lines (and therefore their search patterns) are
identical.</p>
<p>This can be avoided by use of the <code class="docutils literal notranslate"><span class="pre">--excmd=n</span></code> option.</p>
</section>
<section id="bugs">
<h2>BUGS<a class="headerlink" href="#bugs" title="Permalink to this headline">¶</a></h2>
<p>ctags has more options than <code class="docutils literal notranslate"><span class="pre">ls(1)</span></code>.</p>
<p>ctags assumes the input file is written in the correct
grammar. Otherwise output of ctags is undefined. In other words it has garbage
in, garbage out (GIGO) feature.</p>
<p>When parsing a C++ member function definition (e.g. <code class="docutils literal notranslate"><span class="pre">className::function</span></code>),
ctags cannot determine whether the scope specifier
is a class name or a namespace specifier and always lists it as a class name
in the scope portion of the extension fields. Also, if a C++ function
is defined outside of the class declaration (the usual case), the access
specification (i.e. public, protected, or private) and implementation
information (e.g. virtual, pure virtual) contained in the function
declaration are not known when the tag is generated for the function
definition. It will, however be available for prototypes (e.g. <code class="docutils literal notranslate"><span class="pre">--kinds-c++=+p</span></code>).</p>
<p>No qualified tags are generated for language objects inherited into a class.</p>
</section>
<section id="environment-variables">
<h2>ENVIRONMENT VARIABLES<a class="headerlink" href="#environment-variables" title="Permalink to this headline">¶</a></h2>
<dl>
<dt><code class="docutils literal notranslate"><span class="pre">TMPDIR</span></code></dt><dd><p>On Unix-like hosts where <code class="docutils literal notranslate"><span class="pre">mkstemp(3)</span></code> is available, the value of this
variable specifies the directory in which to place temporary files.
This can be useful if the size of a temporary file becomes too large
to fit on the partition holding the default temporary directory
defined at compilation time.</p>
<p>ctags creates temporary
files only if either (1) an emacs-style tag file is being
generated, (2) the tag file is being sent to standard output, or
(3) the program was compiled to use an internal sort algorithm to sort
the tag files instead of the <code class="docutils literal notranslate"><span class="pre">sort(1)</span></code> utility of the operating system.
If the <code class="docutils literal notranslate"><span class="pre">sort(1)</span></code> utility of the operating system is being used, it will
generally observe this variable also.</p>
<p>Note that if ctags
is setuid, the value of <code class="docutils literal notranslate"><span class="pre">TMPDIR</span></code> will be ignored.</p>
</dd>
</dl>
</section>
<section id="files">
<h2>FILES<a class="headerlink" href="#files" title="Permalink to this headline">¶</a></h2>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">tags</span></code></dt><dd><p>The default tag file created by ctags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">TAGS</span></code></dt><dd><p>The default tag file created by etags.</p>
</dd>
</dl>
<p><code class="docutils literal notranslate"><span class="pre">$XDG_CONFIG_HOME/ctags/*.ctags</span></code>, or <code class="docutils literal notranslate"><span class="pre">$HOME/.config/ctags/*.ctags</span></code> if
<code class="docutils literal notranslate"><span class="pre">$XDG_CONFIG_HOME</span></code> is not defined
(on other than MS Windows)</p>
<p><code class="docutils literal notranslate"><span class="pre">$HOME/.ctags.d/*.ctags</span></code></p>
<p><code class="docutils literal notranslate"><span class="pre">$HOMEDRIVE$HOMEPATH/ctags.d/*.ctags</span></code> (on MS Windows only)</p>
<p><code class="docutils literal notranslate"><span class="pre">.ctags.d/*.ctags</span></code></p>
<p><code class="docutils literal notranslate"><span class="pre">ctags.d/*.ctags</span></code></p>
<blockquote>
<div><p>If any of these configuration files exist, each will be expected to
contain a set of default options which are read in the order listed
when ctags starts, but before any command line options
are read. This makes it possible to set up personal or project-level defaults.</p>
<p>It
is possible to compile ctags to read an additional
configuration file before any of those shown above, which will be
indicated if the output produced by the <code class="docutils literal notranslate"><span class="pre">--version</span></code> option lists the
<code class="docutils literal notranslate"><span class="pre">custom-conf</span></code> feature.</p>
<p>Options appearing on the command line will override options
specified in these files. Only options will be read from these
files.</p>
<p>Note that the option
files are read in line-oriented mode in which spaces are significant
(since shell quoting is not possible) but spaces at the beginning
of a line are ignored. Each line of the file is read as
one command line parameter (as if it were quoted with single quotes).
Therefore, use new lines to indicate separate command-line arguments.</p>
<p>A line starting with ‘<code class="docutils literal notranslate"><span class="pre">#</span></code>’ is treated as a comment.</p>
<p><code class="docutils literal notranslate"><span class="pre">*.ctags</span></code> files in a directory are loaded in alphabetical order.</p>
</div></blockquote>
</section>
<section id="see-also">
<h2>SEE ALSO<a class="headerlink" href="#see-also" title="Permalink to this headline">¶</a></h2>
<p>See <a class="reference internal" href="ctags-optlib.7.html#ctags-optlib-7"><span class="std std-ref">ctags-optlib(7)</span></a> for defining (or extending) a parser
in a configuration file.</p>
<p>See <a class="reference internal" href="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a> for the format of tag files.</p>
<p>See <a class="reference internal" href="ctags-incompatibilities.7.html#ctags-incompatibilities-7"><span class="std std-ref">ctags-incompatibilities(7)</span></a> about known incompatible changes
with Exuberant Ctags.</p>
<p>See <a class="reference internal" href="ctags-client-tools.7.html#ctags-client-tools-7"><span class="std std-ref">ctags-client-tools(7)</span></a> if you are interested in writing
a tool for processing tags files.</p>
<p>See <a class="reference internal" href="ctags-lang-python.7.html#ctags-lang-python-7"><span class="std std-ref">ctags-lang-python(7)</span></a> about python input specific notes.</p>
<p>See <a class="reference internal" href="readtags.1.html#readtags-1"><span class="std std-ref">readtags(1)</span></a> about a client tool for binary searching a
name in a sorted tags file.</p>
<p>The official Universal Ctags web site at: <a class="reference external" href="https://ctags.io/">https://ctags.io/</a></p>
<p>Also <code class="docutils literal notranslate"><span class="pre">ex(1)</span></code>, <code class="docutils literal notranslate"><span class="pre">vi(1)</span></code>, <code class="docutils literal notranslate"><span class="pre">elvis(1)</span></code>, or, better yet, <code class="docutils literal notranslate"><span class="pre">vim(1)</span></code>, the official editor of ctags.
For more information on <code class="docutils literal notranslate"><span class="pre">vim(1)</span></code>, see the Vim web site at: <a class="reference external" href="https://www.vim.org/">https://www.vim.org/</a></p>
</section>
<section id="author">
<h2>AUTHOR<a class="headerlink" href="#author" title="Permalink to this headline">¶</a></h2>
<p>Universal Ctags project
<a class="reference external" href="https://ctags.io/">https://ctags.io/</a></p>
<p>Darren Hiebert <<a class="reference external" href="mailto:dhiebert%40users.sourceforge.net">dhiebert<span>@</span>users<span>.</span>sourceforge<span>.</span>net</a>>
<a class="reference external" href="http://DarrenHiebert.com/">http://DarrenHiebert.com/</a></p>
</section>
<section id="motivation">
<h2>MOTIVATION<a class="headerlink" href="#motivation" title="Permalink to this headline">¶</a></h2>
<p>“Think ye at all times of rendering some service to every member of the
human race.”</p>
<p>“All effort and exertion put forth by man from the fullness of his heart is
worship, if it is prompted by the highest motives and the will to do
service to humanity.”</p>
<p>-- From the Baha’i Writings</p>
</section>
<section id="credits">
<h2>CREDITS<a class="headerlink" href="#credits" title="Permalink to this headline">¶</a></h2>
<p>This version of ctags (Universal Ctags) derived from
the repository, known as fishman-ctags, started by Reza Jelveh.</p>
<p>The fishman-ctags was derived from Exuberant Ctags.</p>
<p>Some parsers are taken from <code class="docutils literal notranslate"><span class="pre">tagmanager</span></code> of the Geany (<a class="reference external" href="https://www.geany.org/">https://www.geany.org/</a>)
project.</p>
<p>Exuberant Ctags was originally derived from and
inspired by the ctags program by Steve Kirkendall <<a class="reference external" href="mailto:kirkenda%40cs.pdx.edu">kirkenda<span>@</span>cs<span>.</span>pdx<span>.</span>edu</a>>
that comes with the Elvis vi clone (though virtually none of the original
code remains).</p>
<p>Credit is also due Bram Moolenaar <<a class="reference external" href="mailto:Bram%40vim.org">Bram<span>@</span>vim<span>.</span>org</a>>, the author of vim,
who has devoted so much of his time and energy both to developing the editor
as a service to others, and to helping the orphans of Uganda.</p>
<p>The section entitled “<a class="reference internal" href="#how-to-use-with-gnu-emacs">HOW TO USE WITH GNU EMACS</a>” was shamelessly stolen
from the info page for GNU etags.</p>
</section>
</section>
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<h3><a href="../index.html">Table of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">ctags</a><ul>
<li><a class="reference internal" href="#synopsis">SYNOPSIS</a></li>
<li><a class="reference internal" href="#description">DESCRIPTION</a></li>
<li><a class="reference internal" href="#command-line-interface">COMMAND LINE INTERFACE</a><ul>
<li><a class="reference internal" href="#letters-and-names">Letters and names</a></li>
<li><a class="reference internal" href="#list-options">List options</a></li>
</ul>
</li>
<li><a class="reference internal" href="#options">OPTIONS</a><ul>
<li><a class="reference internal" href="#input-output-file-options">Input/Output File Options</a></li>
<li><a class="reference internal" href="#output-format-options">Output Format Options</a></li>
<li><a class="reference internal" href="#language-selection-and-mapping-options">Language Selection and Mapping Options</a></li>
<li><a class="reference internal" href="#tags-file-contents-options">Tags File Contents Options</a></li>
<li><a class="reference internal" href="#option-file-options">Option File Options</a></li>
<li><a class="reference internal" href="#optlib-options">optlib Options</a></li>
<li><a class="reference internal" href="#language-specific-options">Language Specific Options</a></li>
<li><a class="reference internal" href="#listing-options">Listing Options</a></li>
<li><a class="reference internal" href="#miscellaneous-options">Miscellaneous Options</a></li>
<li><a class="reference internal" href="#obsoleted-options">Obsoleted Options</a></li>
</ul>
</li>
<li><a class="reference internal" href="#operational-details">OPERATIONAL DETAILS</a><ul>
<li><a class="reference internal" href="#notes-for-c-c-parser">Notes for C/C++ Parser</a></li>
<li><a class="reference internal" href="#determining-file-language">Determining file language</a><ul>
<li><a class="reference internal" href="#file-name-mapping">File name mapping</a></li>
<li><a class="reference internal" href="#heuristically-guessing">Heuristically guessing</a></li>
</ul>
</li>
</ul>
</li>
<li><a class="reference internal" href="#tag-file-format">TAG FILE FORMAT</a></li>
<li><a class="reference internal" href="#tag-entries">TAG ENTRIES</a><ul>
<li><a class="reference internal" href="#extension-fields">Extension fields</a><ul>
<li><a class="reference internal" href="#kinds">Kinds</a></li>
<li><a class="reference internal" href="#roles">Roles</a></li>
</ul>
</li>
<li><a class="reference internal" href="#extras">Extras</a></li>
<li><a class="reference internal" href="#language-specific-fields-and-extras">Language-specific fields and extras</a></li>
</ul>
</li>
<li><a class="reference internal" href="#how-to-use-with-vi">HOW TO USE WITH VI</a></li>
<li><a class="reference internal" href="#how-to-use-with-gnu-emacs">HOW TO USE WITH GNU EMACS</a></li>
<li><a class="reference internal" href="#how-to-use-with-nedit">HOW TO USE WITH NEDIT</a></li>
<li><a class="reference internal" href="#caveats">CAVEATS</a></li>
<li><a class="reference internal" href="#bugs">BUGS</a></li>
<li><a class="reference internal" href="#environment-variables">ENVIRONMENT VARIABLES</a></li>
<li><a class="reference internal" href="#files">FILES</a></li>
<li><a class="reference internal" href="#see-also">SEE ALSO</a></li>
<li><a class="reference internal" href="#author">AUTHOR</a></li>
<li><a class="reference internal" href="#motivation">MOTIVATION</a></li>
<li><a class="reference internal" href="#credits">CREDITS</a></li>
</ul>
</li>
</ul>
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