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PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT |
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MV(1P) POSIX Programmer's Manual MV(1P)
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
mv — move files
mv [−if] source_file target_file
mv [−if] source_file... target_dir
In the first synopsis form, the mv utility shall move the file named
by the source_file operand to the destination 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 this case, if source_file
names a non-directory file and target_file ends with a trailing
<slash> character, mv shall treat this as an error and no source_file
operands will be processed.
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 if the target did not end in a
<slash>, and the last pathname component of the source_file. This
second form is assumed when the final operand names an existing
directory.
If any operand specifies an existing file of a type not specified by
the System Interfaces volume of POSIX.1‐2008, the behavior is
implementation-defined.
For each source_file the following steps shall be taken:
1. If the destination path exists, the −f option is not specified,
and either of the following conditions is true:
a. The permissions of the destination path do not permit writing
and the standard input is a terminal.
b. 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 current source_file and go on to
any remaining source_files.
2. If the source_file operand and destination path name the same
existing file, then the destination path shall not be removed,
and one of the following shall occur:
a. No change is made to source_file, no error occurs, and no
diagnostic is issued.
b. No change is made to source_file, a diagnostic is issued to
standard error identifying the two names, and the exit status
is affected.
c. If the source_file operand and destination path name distinct
directory entries, then the source_file operand is removed,
no error occurs, and no diagnostic is issued.
The mv utility shall do nothing more with the current
source_file, and go on to any remaining source_files.
3. The mv utility shall perform actions equivalent to the rename()
function defined in the System Interfaces volume of POSIX.1‐2008,
called with the following arguments:
a. The source_file operand is used as the old argument.
b. The destination path is used as the new argument.
If this succeeds, mv shall do nothing more with the current
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 POSIX.1‐2008, 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.
4. If the destination path exists, and it is a file of type
directory and source_file is not a file of type directory, 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 and was
created by a previous step, it is unspecified whether this will
treated as an error or the destination path will be overwritten.
5. 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.
6. The file hierarchy rooted in source_file shall be duplicated 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 characteristics of each file in the file hierarchy
shall be duplicated:
* 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 files being duplicated to another file system have hard links
to other files, it is unspecified whether the files copied to the
new file system have the hard links preserved or separate copies
are created for the linked files.
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 standard error,
but this failure shall not cause mv to modify its exit status.
7. 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.
The mv utility shall conform to the Base Definitions volume of
POSIX.1‐2008, 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.
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.
The standard input shall be used to read an input line in response to
each prompt specified in the STDERR section. Otherwise, the standard
input shall not be used.
The input files specified by each source_file operand can be of any
file type.
The following environment variables shall affect the execution of mv:
LANG Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions
volume of POSIX.1‐2008, Section 8.2, Internationalization
Variables for the precedence of internationalization
variables used to determine the values of locale
categories.)
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 collating elements
used in the extended regular expression 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 category.
LC_MESSAGES
Determine the locale used to process affirmative responses,
and the locale used to affect the format and contents of
diagnostic messages and prompts written to standard error.
NLSPATH Determine the location of message catalogs for the
processing of LC_MESSAGES.
Default.
Not used.
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
messages.
The output files may be of any file type.
None.
The following exit values shall be returned:
0 All input files were moved successfully.
>0 An error occurred.
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 destination path simultaneously; termination at
any point shall leave either source_file or the destination path
complete.
The following sections are informative.
Some implementations mark for update the last file status change
timestamp of renamed files and some do not. Applications which make
use of the last file status change timestamp may behave differently
with respect to renamed files unless they are designed to allow for
either behavior.
The specification ensures that mv a a will not alter the contents of
file a, and allows the implementation to issue an error that a file
cannot be moved onto itself. Likewise, when a and b are hard links to
the same file, mv a b will not alter b, but if a diagnostic is not
issued, then it is unspecified whether a is left untouched (as it
would be by the rename() function) or unlinked (reducing the link
count of b).
If the current directory contains only files a (of any type defined
by the System Interfaces volume of POSIX.1‐2008), 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.
Early proposals diverged from the SVID and BSD historical practice in
that they required that when the destination 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
historical practice. It should be noted that this is consistent with
the rename() function defined in the System Interfaces volume of
POSIX.1‐2008, 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 destination 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 different file system. The standard
developers considered that this was an annoying inconsistency, so
this volume of POSIX.1‐2008 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 directories 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 systems, 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 unspecified. Only the
general nature of the contents of prompts are specified because
implementations may desire more descriptive prompts than those used
on historical implementations. 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() functionality, per the DESCRIPTION. Across
file systems, this has to be made explicit.
None.
cp(1p), ln(1p)
The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
Variables, Section 12.2, Utility Syntax Guidelines
The System Interfaces volume of POSIX.1‐2008, rename(3p)
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) 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.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 MV(1P)
Pages that refer to this page: cp(1p), find(1p)
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