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<section id="readtags">
<span id="readtags-1"></span><h1>readtags<a class="headerlink" href="#readtags" title="Permalink to this headline">¶</a></h1>
<p>Find tag file entries matching specified names</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>readtags</strong> -h | --help</div>
<div class="line"><strong>readtags</strong> (-H | --help-expression) (filter|sorter)</div>
<div class="line"><strong>readtags</strong> [OPTION]… ACTION</div>
</div>
</section>
<section id="description">
<h2>DESCRIPTION<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
<p>The <strong>readtags</strong> program filters, sorts and prints tag entries in a tags file.
The basic filtering is done using <strong>actions</strong>, by which you can list all
regular tags, pseudo tags or regular tags matching specific name. Then, further
filtering and sorting can be done using <strong>post processors</strong>, namely <strong>filter
expressions</strong> and <strong>sorter expressions</strong>.</p>
</section>
<section id="actions">
<h2>ACTIONS<a class="headerlink" href="#actions" title="Permalink to this headline">¶</a></h2>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">-l</span></code>, <code class="docutils literal notranslate"><span class="pre">--list</span></code></dt><dd><p>List regular tags.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">[-]</span> <span class="pre">NAME</span></code></dt><dd><p>List regular tags matching NAME.
“-” as NAME indicates arguments after this as NAME even if they start with -.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-D</span></code>, <code class="docutils literal notranslate"><span class="pre">--list-pseudo-tags</span></code></dt><dd><p>Equivalent to <code class="docutils literal notranslate"><span class="pre">--list-pseudo-tags</span></code>.</p>
</dd>
</dl>
</section>
<section id="options">
<h2>OPTIONS<a class="headerlink" href="#options" title="Permalink to this headline">¶</a></h2>
<section id="controlling-the-tags-reading-behavior">
<h3>Controlling the Tags Reading Behavior<a class="headerlink" href="#controlling-the-tags-reading-behavior" title="Permalink to this headline">¶</a></h3>
<p>The behavior of reading tags can be controlled using these options:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">-t</span> <span class="pre">TAGFILE</span></code>, <code class="docutils literal notranslate"><span class="pre">--tag-file</span> <span class="pre">TAGFILE</span></code></dt><dd><p>Use specified tag file (default: “tags”).</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-s[0|1|2]</span></code>, <code class="docutils literal notranslate"><span class="pre">--override-sort-detection</span> <span class="pre">METHOD</span></code></dt><dd><p>Override sort detection of tag file.
METHOD: unsorted|sorted|foldcase</p>
</dd>
</dl>
<p>The NAME action will perform binary search on sorted (including “foldcase”)
tags files, which is much faster then on unsorted tags files.</p>
</section>
<section id="controlling-the-name-action-behavior">
<h3>Controlling the NAME Action Behavior<a class="headerlink" href="#controlling-the-name-action-behavior" title="Permalink to this headline">¶</a></h3>
<p>The behavior of the NAME action can be controlled using these options:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">-i</span></code>, <code class="docutils literal notranslate"><span class="pre">--icase-match</span></code></dt><dd><p>Perform case-insensitive matching in the NAME action.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-p</span></code>, <code class="docutils literal notranslate"><span class="pre">--prefix-match</span></code></dt><dd><p>Perform prefix matching in the NAME action.</p>
</dd>
</dl>
</section>
<section id="controlling-the-output">
<h3>Controlling the Output<a class="headerlink" href="#controlling-the-output" title="Permalink to this headline">¶</a></h3>
<p>By default, the output of readtags contains only the name, input and pattern
field. The Output can be tweaked using these options:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">-d</span></code>, <code class="docutils literal notranslate"><span class="pre">--debug</span></code></dt><dd><p>Turn on debugging output.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-E</span></code>, <code class="docutils literal notranslate"><span class="pre">--escape-output</span></code></dt><dd><p>Escape characters like tabs in output as described in <a class="reference internal" href="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a>.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-e</span></code>, <code class="docutils literal notranslate"><span class="pre">--extension-fields</span></code></dt><dd><p>Include extension fields in output.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-n</span></code>, <code class="docutils literal notranslate"><span class="pre">--line-number</span></code></dt><dd><p>Also include the line number field when <code class="docutils literal notranslate"><span class="pre">-e</span></code> option is give.</p>
</dd>
</dl>
<p>About the <code class="docutils literal notranslate"><span class="pre">-E</span></code> option: certain characters are escaped in a tags file, to make
it machine-readable. e.g., ensuring no tabs character appear in fields other
than the pattern field. By default, readtags translates them to make it
human-readable, but when utilizing readtags output in a script or a client
tool, <code class="docutils literal notranslate"><span class="pre">-E</span></code> option should be used. 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
discussion on this.</p>
</section>
<section id="filtering-and-sorting">
<h3>Filtering and Sorting<a class="headerlink" href="#filtering-and-sorting" title="Permalink to this headline">¶</a></h3>
<p>Further filtering and sorting on the tags listed by actions are performed using:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">-Q</span> <span class="pre">EXP</span></code>, <code class="docutils literal notranslate"><span class="pre">--filter</span> <span class="pre">EXP</span></code></dt><dd><p>Filter the tags listed by ACTION with EXP before printing.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">-S</span> <span class="pre">EXP</span></code>, <code class="docutils literal notranslate"><span class="pre">--sorter</span> <span class="pre">EXP</span></code></dt><dd><p>Sort the tags listed by ACTION with EXP before printing.</p>
</dd>
</dl>
<p>These are discussed in the <a class="reference internal" href="#expression">EXPRESSION</a> section.</p>
</section>
<section id="examples">
<h3>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h3>
<ul>
<li><p>List all tags in “/path/to/tags”:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -t /path/to/tags -l
</pre></div>
</div>
</li>
<li><p>List all tags in “tags” that start with “mymethod”:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -p - mymethod
</pre></div>
</div>
</li>
<li><p>List all tags matching “mymethod”, case insensitively:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -i - mymethod
</pre></div>
</div>
</li>
<li><p>List all tags start with “myvar”, and printing all fields (i.e., the whole line):</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -p -ne - myvar
</pre></div>
</div>
</li>
</ul>
</section>
</section>
<section id="expression">
<h2>EXPRESSION<a class="headerlink" href="#expression" title="Permalink to this headline">¶</a></h2>
<p>Scheme-style expressions are used for the <code class="docutils literal notranslate"><span class="pre">-Q</span></code> and <code class="docutils literal notranslate"><span class="pre">-S</span></code> options. For those
who doesn’t know Scheme or Lisp, just remember:</p>
<ul class="simple">
<li><p>A function call is wrapped in a pair of parenthesis. The first item in it is
the function/operator name, the others are arguments.</p></li>
<li><p>Function calls can be nested.</p></li>
<li><p>Missing values and boolean false are represented by <code class="docutils literal notranslate"><span class="pre">#f</span></code>. <code class="docutils literal notranslate"><span class="pre">#t</span></code> and all
other values are considered to be true.</p></li>
</ul>
<p>So, <code class="docutils literal notranslate"><span class="pre">(+</span> <span class="pre">1</span> <span class="pre">(+</span> <span class="pre">2</span> <span class="pre">3))</span></code> means add 2 and 3 first, then add the result with 1.
<code class="docutils literal notranslate"><span class="pre">(and</span> <span class="pre">"string"</span> <span class="pre">1</span> <span class="pre">#t)</span></code> means logical AND on <code class="docutils literal notranslate"><span class="pre">"string"</span></code>, <code class="docutils literal notranslate"><span class="pre">1</span></code> and <code class="docutils literal notranslate"><span class="pre">#t</span></code>,
and the result is true since there is no <code class="docutils literal notranslate"><span class="pre">#f</span></code>.</p>
<section id="filtering">
<h3>Filtering<a class="headerlink" href="#filtering" title="Permalink to this headline">¶</a></h3>
<p>The tag entries that make the filter expression produces true value are printed
by readtags.</p>
<p>The basic operators for filtering are <code class="docutils literal notranslate"><span class="pre">eq?</span></code>, <code class="docutils literal notranslate"><span class="pre">prefix?</span></code>, <code class="docutils literal notranslate"><span class="pre">suffix?</span></code>,
<code class="docutils literal notranslate"><span class="pre">substr?</span></code>, and <code class="docutils literal notranslate"><span class="pre">#/PATTERN/</span></code>. Language common fields can be accessed using
variables starting with <code class="docutils literal notranslate"><span class="pre">$</span></code>, e.g., <code class="docutils literal notranslate"><span class="pre">$language</span></code> represents the language field.
For example:</p>
<ul>
<li><p>List all tags start with “myfunc” in Python code files:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -p -Q <span class="s1">'(eq? $language "Python")'</span> - myfunc
</pre></div>
</div>
</li>
</ul>
<p><code class="docutils literal notranslate"><span class="pre">downcase</span></code> or <code class="docutils literal notranslate"><span class="pre">upcase</span></code> operators can be used to perform case-insensitive
matching:</p>
<ul>
<li><p>List all tags containing “my”, case insensitively:</p>
<blockquote>
<div><div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(substr? (downcase $name) "my")'</span> -l
</pre></div>
</div>
</div></blockquote>
</li>
</ul>
<p>We have logical operators like <code class="docutils literal notranslate"><span class="pre">and</span></code>, <code class="docutils literal notranslate"><span class="pre">or</span></code> and <code class="docutils literal notranslate"><span class="pre">not</span></code>. The value of a
missing field is #f, so we could deal with missing fields:</p>
<ul>
<li><p>List all tags containing “impl” in Python code files, but allow the
<code class="docutils literal notranslate"><span class="pre">language:</span></code> field to be missing:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span>$ readtags -Q '(and (substr? $name "impl")\
(or (not $language)\
(eq? $language "Python")))' -l
</pre></div>
</div>
</li>
</ul>
<p><code class="docutils literal notranslate"><span class="pre">#/PATTERN/</span></code> is for the case when string predicates (<code class="docutils literal notranslate"><span class="pre">prefix?</span></code>, <code class="docutils literal notranslate"><span class="pre">suffix?</span></code>,
and <code class="docutils literal notranslate"><span class="pre">substr?</span></code>) are not enough. You can use “Posix extended regular expression”
as PATTERN.</p>
<ul>
<li><p>List all tags inherits from the class “A”:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(#/(^|,) ?A(,|$)/ $inherits)'</span> -l
</pre></div>
</div>
</li>
</ul>
<p>Here <code class="docutils literal notranslate"><span class="pre">$inherits</span></code> is a comma-separated class list like “A,B,C”, “P, A, Q”, or
just “A”. Notice that this filter works on both situations where there’s a
space after each comma or there’s not.</p>
<p>Case-insensitive matching can be performed by <code class="docutils literal notranslate"><span class="pre">#/PATTERN/i</span></code>:</p>
<ul>
<li><p>List all tags inherits from the class “A” or “a”:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(#/(^|,) ?A(,|$)/i $inherits)'</span> -l
</pre></div>
</div>
</li>
</ul>
<p>To include “/” in a pattern, prefix <code class="docutils literal notranslate"><span class="pre">\</span></code> to the “/”.</p>
<p>NOTE: The above regular expression pattern for inspecting inheritances is just
an example to show how to use <code class="docutils literal notranslate"><span class="pre">#/PATTERN/</span></code> expression. Tags file generators
have no consensus about the format of <code class="docutils literal notranslate"><span class="pre">inherits:</span></code>, e.g., whether there should
be a space after a comma. Even parsers in ctags have no consensus. Noticing the
format of the <code class="docutils literal notranslate"><span class="pre">inherits:</span></code> field of specific languages is needed for such
queries.</p>
<p>The expressions <code class="docutils literal notranslate"><span class="pre">#/PATTERN/</span></code> and <code class="docutils literal notranslate"><span class="pre">#/PATTERN/i</span></code> are for interactive use.
Readtags also offers an alias <code class="docutils literal notranslate"><span class="pre">string->regexp</span></code>, so <code class="docutils literal notranslate"><span class="pre">#/PATTERN/</span></code> is equal to
<code class="docutils literal notranslate"><span class="pre">(string->regexp</span> <span class="pre">"PATTERN")</span></code>, and <code class="docutils literal notranslate"><span class="pre">#/PATTERN/i</span></code> is equal to
<code class="docutils literal notranslate"><span class="pre">(string->regexp</span> <span class="pre">"PATTERN"</span> <span class="pre">:case-fold</span> <span class="pre">#t)</span></code>. <code class="docutils literal notranslate"><span class="pre">string->regexp</span></code> doesn’t need
to prefix <code class="docutils literal notranslate"><span class="pre">\</span></code> for including “/” in a pattern. <code class="docutils literal notranslate"><span class="pre">string->regexp</span></code> may simplify
a client tool building an expression. See also <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
building expressions in your tool.</p>
<p>Let’s now consider missing fields. The tags file may have tag entries that has
no <code class="docutils literal notranslate"><span class="pre">inherits:</span></code> field. In that case <code class="docutils literal notranslate"><span class="pre">$inherits</span></code> is #f, and the regular
expression matching raises an error, since string operators only work for
strings. To avoid this problem:</p>
<ul>
<li><p>Safely list all tags inherits from the class “A”:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(and $inherits (#/(^|,) ?A(,|$)/ $inherits))'</span> -l
</pre></div>
</div>
</li>
</ul>
<p>This makes sure <code class="docutils literal notranslate"><span class="pre">$inherits</span></code> is not missing first, then match it by regexp.</p>
<p>Sometimes you want to keep tags where the field <em>is</em> missing. For example, your
want to exclude reference tags, which is marked by the <code class="docutils literal notranslate"><span class="pre">extras:</span></code> field, then
you want to keep tags who doesn’t have <code class="docutils literal notranslate"><span class="pre">extras:</span></code> field since they are also
not reference tags. Here’s how to do it:</p>
<ul>
<li><p>List all tags but the reference tags:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(or (not $extras) (#/(^|,) ?reference(,|$)/ $extras))'</span> -l
</pre></div>
</div>
</li>
</ul>
<p>Notice that <code class="docutils literal notranslate"><span class="pre">(not</span> <span class="pre">$extras)</span></code> produces <code class="docutils literal notranslate"><span class="pre">#t</span></code> when <code class="docutils literal notranslate"><span class="pre">$extras</span></code> is missing, so
the whole <code class="docutils literal notranslate"><span class="pre">or</span></code> expression produces <code class="docutils literal notranslate"><span class="pre">#t</span></code>.</p>
<p>Run “readtags -H filter” to know about all valid functions and variables.</p>
</section>
<section id="sorting">
<h3>Sorting<a class="headerlink" href="#sorting" title="Permalink to this headline">¶</a></h3>
<p>When sorting, the sorter expression is evaluated on two tag entries to decide
which should sort before the other one, until the order of all tag entries is
decided.</p>
<p>In a sorter expression, <code class="docutils literal notranslate"><span class="pre">$</span></code> and <code class="docutils literal notranslate"><span class="pre">&</span></code> are used to access the fields in the
two tag entries, and let’s call them $-entry and &-entry. The sorter expression
should have a value of -1, 0 or 1. The value -1 means the $-entry should be put
above the &-entry, 1 means the contrary, and 0 makes their order in the output
uncertain.</p>
<p>The core operator of sorting is <code class="docutils literal notranslate"><span class="pre"><></span></code>. It’s used to compare two strings or two
numbers (numbers are for the <code class="docutils literal notranslate"><span class="pre">line:</span></code> or <code class="docutils literal notranslate"><span class="pre">end:</span></code> fields). In <code class="docutils literal notranslate"><span class="pre">(<></span> <span class="pre">a</span> <span class="pre">b)</span></code>, if
<code class="docutils literal notranslate"><span class="pre">a</span></code> < <code class="docutils literal notranslate"><span class="pre">b</span></code>, the result is -1; <code class="docutils literal notranslate"><span class="pre">a</span></code> > <code class="docutils literal notranslate"><span class="pre">b</span></code> produces 1, and <code class="docutils literal notranslate"><span class="pre">a</span></code> = <code class="docutils literal notranslate"><span class="pre">b</span></code>
produces 0. Strings are compared using the <code class="docutils literal notranslate"><span class="pre">strcmp</span></code> function, see strcmp(3).</p>
<p>For example, sort by names, and make those shorter or alphabetically smaller
ones appear before the others:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -S <span class="s1">'(<> $name &name)'</span> -l
</pre></div>
</div>
<p>This reads “If the tag name in the $-entry is smaller, it goes before the
&-entry”.</p>
<p>The <code class="docutils literal notranslate"><span class="pre"><or></span></code> operator is used to chain multiple expressions until one returns
-1 or 1. For example, sort by input file names, then line numbers if in the
same file:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -S <span class="s1">'(<or> (<> $input &input) (<> $line &line))'</span> -l
</pre></div>
</div>
<p>The <code class="docutils literal notranslate"><span class="pre">*-</span></code> operator is used to flip the compare result. i.e., <code class="docutils literal notranslate"><span class="pre">(*-</span> <span class="pre">(<></span> <span class="pre">a</span> <span class="pre">b))</span></code>
is the same as <code class="docutils literal notranslate"><span class="pre">(<></span> <span class="pre">b</span> <span class="pre">a)</span></code>.</p>
<p>Filter expressions can be used in sorter expressions. The technique is use
<code class="docutils literal notranslate"><span class="pre">if</span></code> to produce integers that can be compared based on the filter, like:</p>
<div class="highlight-lisp notranslate"><div class="highlight"><pre><span></span><span class="p">(</span><span class="nv"><></span> <span class="p">(</span><span class="k">if</span> <span class="nv">filter-expr-on-$-entry</span> <span class="mi">-1</span> <span class="mi">1</span><span class="p">)</span>
<span class="p">(</span><span class="k">if</span> <span class="nv">filter-expr-on-&-entry</span> <span class="mi">-1</span> <span class="mi">1</span><span class="p">))</span>
</pre></div>
</div>
<p>So if $-entry satisfies the filter, while &-entry doesn’t, it’s the same as
<code class="docutils literal notranslate"><span class="pre">(<></span> <span class="pre">-1</span> <span class="pre">1)</span></code>, which produces <code class="docutils literal notranslate"><span class="pre">-1</span></code>.</p>
<p>For example, we want to put tags with “file” kind below other tags, then the
sorter would look like:</p>
<div class="highlight-lisp notranslate"><div class="highlight"><pre><span></span><span class="p">(</span><span class="nv"><></span> <span class="p">(</span><span class="k">if</span> <span class="p">(</span><span class="nv">eq?</span> <span class="nv">$kind</span> <span class="s">"file"</span><span class="p">)</span> <span class="mi">1</span> <span class="mi">-1</span><span class="p">)</span>
<span class="p">(</span><span class="k">if</span> <span class="p">(</span><span class="nv">eq?</span> <span class="nv">&kind</span> <span class="s">"file"</span><span class="p">)</span> <span class="mi">1</span> <span class="mi">-1</span><span class="p">))</span>
</pre></div>
</div>
<p>A quick read tells us: If $-entry has “file” kind, and &-entry doesn’t, the
sorter becomes <code class="docutils literal notranslate"><span class="pre">(<></span> <span class="pre">1</span> <span class="pre">-1)</span></code>, which produces <code class="docutils literal notranslate"><span class="pre">1</span></code>, so the $-entry is put below
the &-entry, exactly what we want.</p>
</section>
<section id="inspecting-the-behavior-of-expressions">
<h3>Inspecting the Behavior of Expressions<a class="headerlink" href="#inspecting-the-behavior-of-expressions" title="Permalink to this headline">¶</a></h3>
<p>The <cite>print</cite> operator can be used to print the value of an expression. For
example:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(print $name)'</span> -l
</pre></div>
</div>
<p>prints the name of each tag entry before it. Since the return value of
<code class="docutils literal notranslate"><span class="pre">print</span></code> is not #f, all the tag entries are printed. We could control this
using the <code class="docutils literal notranslate"><span class="pre">begin</span></code> or <code class="docutils literal notranslate"><span class="pre">begin0</span></code> operator. <code class="docutils literal notranslate"><span class="pre">begin</span></code> returns the value of its
last argument, and <code class="docutils literal notranslate"><span class="pre">begin0</span></code> returns the value of its first argument. For
example:</p>
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>readtags -Q <span class="s1">'(begin0 #f (print (prefix? "ctags" "ct")))'</span> -l
</pre></div>
</div>
<p>prints a bunch of “#t” (depending on how many lines are in the tags file), and
the actual tag entries are not printed.</p>
</section>
</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="tags.5.html#tags-5"><span class="std std-ref">tags(5)</span></a> for the details of tags file format.</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> for the tips writing a
tool utilizing tags file.</p>
<p>The official Universal Ctags web site at:</p>
<p><a class="reference external" href="https://ctags.io/">https://ctags.io/</a></p>
<p>The git repository for the library used in readtags command:</p>
<p><a class="reference external" href="https://github.com/universal-ctags/libreadtags">https://github.com/universal-ctags/libreadtags</a></p>
</section>
<section id="credits">
<h2>CREDITS<a class="headerlink" href="#credits" 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>
<p>The readtags command and libreadtags maintained at Universal Ctags
are derived from readtags.c and readtags.h developd at
<a class="reference external" href="http://ctags.sourceforge.net">http://ctags.sourceforge.net</a>.</p>
</section>
</section>
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<h3><a href="../index.html">Table of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">readtags</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="#actions">ACTIONS</a></li>
<li><a class="reference internal" href="#options">OPTIONS</a><ul>
<li><a class="reference internal" href="#controlling-the-tags-reading-behavior">Controlling the Tags Reading Behavior</a></li>
<li><a class="reference internal" href="#controlling-the-name-action-behavior">Controlling the NAME Action Behavior</a></li>
<li><a class="reference internal" href="#controlling-the-output">Controlling the Output</a></li>
<li><a class="reference internal" href="#filtering-and-sorting">Filtering and Sorting</a></li>
<li><a class="reference internal" href="#examples">Examples</a></li>
</ul>
</li>
<li><a class="reference internal" href="#expression">EXPRESSION</a><ul>
<li><a class="reference internal" href="#filtering">Filtering</a></li>
<li><a class="reference internal" href="#sorting">Sorting</a></li>
<li><a class="reference internal" href="#inspecting-the-behavior-of-expressions">Inspecting the Behavior of Expressions</a></li>
</ul>
</li>
<li><a class="reference internal" href="#see-also">SEE ALSO</a></li>
<li><a class="reference internal" href="#credits">CREDITS</a></li>
</ul>
</li>
</ul>
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