mv(P) mv(P)
NAME
mv - move files
SYNOPSIS
mv [-fi] source_file target_file
mv [-fi] source_file... target_file
DESCRIPTION
In the first synopsis form, the mv utility shall move
the file named by the source_file operand to the desti-
nation specified by the target_file. This first synopsis
form is assumed when the final operand does not name an
existing directory and is not a symbolic link referring
to an existing directory.
In the second synopsis form, mv shall move each file
named by a source_file operand to a destination file in
the existing directory named by the target_dir operand,
or referenced if target_dir is a symbolic link referring
to an existing directory. The destination path for each
source_file shall be the concatenation of the target
directory, a single slash character, and the last path-
name component of the source_file. This second form is
assumed when the final operand names an existing direc-
tory.
If any operand specifies an existing file of a type not
specified by the System Interfaces volume of
IEEE Std 1003.1-2001, the behavior is implementation-
defined.
For each source_file the following steps shall be taken:
If the destination path exists, the -f option is not
specified, and either of the following conditions is
true:
The permissions of the destination path do not permit
writing and the standard input is a terminal.
The -i option is specified.
the mv utility shall write a prompt to standard error
and read a line from standard input. If the response is
not affirmative, mv shall do nothing more with the cur-
rent source_file and go on to any remaining
source_files.
The mv utility shall perform actions equivalent to the
rename() function defined in the System Interfaces vol-
ume of IEEE Std 1003.1-2001, called with the following
arguments:
The source_file operand is used as the old argument.
The destination path is used as the new argument.
If this succeeds, mv shall do nothing more with the cur-
rent source_file and go on to any remaining
source_files. If this fails for any reasons other than
those described for the errno [EXDEV] in the System
Interfaces volume of IEEE Std 1003.1-2001, mv shall
write a diagnostic message to standard error, do nothing
more with the current source_file, and go on to any
remaining source_files.
If the destination path exists, and it is a file of type
directory and source_file is not a file of type direc-
tory, or it is a file not of type directory and
source_file is a file of type directory, mv shall write
a diagnostic message to standard error, do nothing more
with the current source_file, and go on to any remaining
source_files.
If the destination path exists, mv shall attempt to
remove it. If this fails for any reason, mv shall write
a diagnostic message to standard error, do nothing more
with the current source_file, and go on to any remaining
source_files.
The file hierarchy rooted in source_file shall be dupli-
cated as a file hierarchy rooted in the destination
path. If source_file or any of the files below it in the
hierarchy are symbolic links, the links themselves shall
be duplicated, including their contents, rather than any
files to which they refer. The following characteris-
tics of each file in the file hierarchy shall be dupli-
cated:
The time of last data modification and time of
last access
The user ID and group ID
The file mode
If the user ID, group ID, or file mode of a regular file
cannot be duplicated, the file mode bits S_ISUID and
S_ISGID shall not be duplicated.
When files are duplicated to another file system, the
implementation may require that the process invoking mv
has read access to each file being duplicated.
If the duplication of the file hierarchy fails for any
reason, mv shall write a diagnostic message to standard
error, do nothing more with the current source_file, and
go on to any remaining source_files.
If the duplication of the file characteristics fails for
any reason, mv shall write a diagnostic message to stan-
dard error, but this failure shall not cause mv to mod-
ify its exit status.
The file hierarchy rooted in source_file shall be
removed. If this fails for any reason, mv shall write a
diagnostic message to the standard error, do nothing
more with the current source_file, and go on to any
remaining source_files.
OPTIONS
The mv utility shall conform to the Base Definitions
volume of IEEE Std 1003.1-2001, Section 12.2, Utility
Syntax Guidelines.
The following options shall be supported:
-f Do not prompt for confirmation if the destination
path exists. Any previous occurrence of the -i
option is ignored.
-i Prompt for confirmation if the destination path
exists. Any previous occurrence of the -f option
is ignored.
Specifying more than one of the -f or -i options shall
not be considered an error. The last option specified
shall determine the behavior of mv.
OPERANDS
The following operands shall be supported:
source_file
A pathname of a file or directory to be moved.
target_file
A new pathname for the file or directory being
moved.
target_dir
A pathname of an existing directory into which to
move the input files.
STDIN
The standard input shall be used to read an input line
in response to each prompt specified in the STDERR sec-
tion. Otherwise, the standard input shall not be used.
INPUT FILES
The input files specified by each source_file operand
can be of any file type.
ENVIRONMENT VARIABLES
The following environment variables shall affect the
execution of mv:
LANG Provide a default value for the internationaliza-
tion variables that are unset or null. (See the
Base Definitions volume of IEEE Std 1003.1-2001,
Section 8.2, Internationalization Variables for
the precedence of internationalization variables
used to determine the values of locale cate-
gories.)
LC_ALL If set to a non-empty string value, override the
values of all the other internationalization
variables.
LC_COLLATE
Determine the locale for the behavior of ranges,
equivalence classes, and multi-character collat-
ing elements used in the extended regular expres-
sion defined for the yesexpr locale keyword in
the LC_MESSAGES category.
LC_CTYPE
Determine the locale for the interpretation of
sequences of bytes of text data as characters
(for example, single-byte as opposed to multi-
byte characters in arguments and input files),
the behavior of character classes used in the
extended regular expression defined for the
yesexpr locale keyword in the LC_MESSAGES cate-
gory.
LC_MESSAGES
Determine the locale for the processing of affir-
mative responses that should be used to affect
the format and contents of diagnostic messages
written to standard error.
NLSPATH
Determine the location of message catalogs for
the processing of LC_MESSAGES .
ASYNCHRONOUS EVENTS
Default.
STDOUT
Not used.
STDERR
Prompts shall be written to the standard error under the
conditions specified in the DESCRIPTION section. The
prompts shall contain the destination pathname, but
their format is otherwise unspecified. Otherwise, the
standard error shall be used only for diagnostic mes-
sages.
OUTPUT FILES
The output files may be of any file type.
EXTENDED DESCRIPTION
None.
EXIT STATUS
The following exit values shall be returned:
0 All input files were moved successfully.
>0 An error occurred.
CONSEQUENCES OF ERRORS
If the copying or removal of source_file is prematurely
terminated by a signal or error, mv may leave a partial
copy of source_file at the source or destination. The mv
utility shall not modify both source_file and the desti-
nation path simultaneously; termination at any point
shall leave either source_file or the destination path
complete.
The following sections are informative.
APPLICATION USAGE
Some implementations mark for update the st_ctime field
of renamed files and some do not. Applications which
make use of the st_ctime field may behave differently
with respect to renamed files unless they are designed
to allow for either behavior.
EXAMPLES
If the current directory contains only files a (of any
type defined by the System Interfaces volume of
IEEE Std 1003.1-2001), b (also of any type), and a
directory c:
mv a b c
mv c d
results with the original files a and b residing in the
directory d in the current directory.
RATIONALE
Early proposals diverged from the SVID and BSD histori-
cal practice in that they required that when the desti-
nation path exists, the -f option is not specified, and
input is not a terminal, mv fails. This was done for
compatibility with cp. The current text returns to his-
torical practice. It should be noted that this is con-
sistent with the rename() function defined in the System
Interfaces volume of IEEE Std 1003.1-2001, which does
not require write permission on the target.
For absolute clarity, paragraph (1), describing the
behavior of mv when prompting for confirmation, should
be interpreted in the following manner:
if (exists AND (NOT f_option) AND
((not_writable AND input_is_terminal) OR i_option))
The -i option exists on BSD systems, giving applications
and users a way to avoid accidentally unlinking files
when moving others. When the standard input is not a
terminal, the 4.3 BSD mv deletes all existing destina-
tion paths without prompting, even when -i is specified;
this is inconsistent with the behavior of the 4.3 BSD cp
utility, which always generates an error when the file
is unwritable and the standard input is not a terminal.
The standard developers decided that use of -i is a
request for interaction, so when the destination path
exists, the utility takes instructions from whatever
responds to standard input.
The rename() function is able to move directories within
the same file system. Some historical versions of mv
have been able to move directories, but not to a differ-
ent file system. The standard developers considered that
this was an annoying inconsistency, so this volume of
IEEE Std 1003.1-2001 requires directories to be able to
be moved even across file systems. There is no -R option
to confirm that moving a directory is actually intended,
since such an option was not required for moving direc-
tories in historical practice. Requiring the application
to specify it sometimes, depending on the destination,
seemed just as inconsistent. The semantics of the
rename() function were preserved as much as possible.
For example, mv is not permitted to "rename" files to or
from directories, even though they might be empty and
removable.
Historic implementations of mv did not exit with a non-
zero exit status if they were unable to duplicate any
file characteristics when moving a file across file sys-
tems, nor did they write a diagnostic message for the
user. The former behavior has been preserved to prevent
scripts from breaking; a diagnostic message is now
required, however, so that users are alerted that the
file characteristics have changed.
The exact format of the interactive prompts is unspeci-
fied. Only the general nature of the contents of prompts
are specified because implementations may desire more
descriptive prompts than those used on historical imple-
mentations. Therefore, an application not using the -f
option or using the -i option relies on the system to
provide the most suitable dialog directly with the user,
based on the behavior specified.
When mv is dealing with a single file system and
source_file is a symbolic link, the link itself is moved
as a consequence of the dependence on the rename() func-
tionality, per the DESCRIPTION. Across file systems,
this has to be made explicit.
FUTURE DIRECTIONS
None.
SEE ALSO
cp , ln , the System Interfaces volume of
IEEE Std 1003.1-2001, rename()
COPYRIGHT
Portions of this text are reprinted and reproduced in
electronic form from IEEE Std 1003.1, 2003 Edition,
Standard for Information Technology -- Portable Operat-
ing System Interface (POSIX), The Open Group Base Speci-
fications Issue 6, Copyright (C) 2001-2003 by the Insti-
tute of Electrical and Electronics Engineers, Inc and
The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group
Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be
obtained online at http://www.open-
group.org/unix/online.html .
POSIX 2003 mv(P)