In the first synopsis form, the mv utility moves the file named by the source operand to the destination specified by the target_file. source and target_file may not have the same name. If target_file does not exist, mv creates a file named target_file. If target_file exists, its contents are overwritten. This first synopsis form is assumed when the final operand does not name an existing directory.

In the second synopsis form, mv moves each file named by a source operand to a destination file in the existing directory named by the target_dir operand. The destination path for each source is the concatenation of the target directory, a single slash character (/), and the last path name component of the source. This second form is assumed when the final operand names an existing directory.

If mv determines that the mode of target_file forbids writing, it will print the mode (see chmod(2)), ask for a response, and read the standard input for one line. If the response is affirmative, the mv occurs, if permissible; otherwise, the command exits. Notice that the mode displayed may not fully represent the access permission if target is associated with an ACL. When the parent directory of source is writable and has the sticky bit set, one or more of the following conditions must be true:

• the user must own the file
• the user must own the directory
• the file must be writable by the user
• the user must be a privileged user

If source is a file and target_file is a link to another file with links, the other links remain and target_file becomes a new file.

If source and target_file/target_dir are on different file systems, mv copies the source and deletes the original. Any hard links to other files are lost. mv will attempt to duplicate the source file characteristics to the target, that is, the owner and group id, permission modes, modification and access times, ACLs, and extended attributes, if applicable. For symbolic links, mv will preserve only the owner and group of the link itself.

If unable to preserve owner and group id, mv will clear S_ISUID and S_ISGID bits in the target. mv will print a diagnostic message to stderr if unable to clear these bits, though the exit code will not be affected. mv may be unable to preserve extended attributes if the target file system does not have extended attribute support. /usr/xpg4/bin/mv will print a diagnostic message to stderr for all other failed attempts to duplicate file characteristics. The exit code will not be affected.

In order to preserve the source file characteristics, users must have the appropriate file access permissions. This includes being super-user or having the same owner id as the destination file.

The following options are supported:

-f

mv will move the file(s) without prompting even if it is writing over an existing target. Note that this is the default if the standard input is not a terminal.

-i

mv will prompt for confirmation whenever the move would overwrite an existing target. An affirmative answer means that the move should proceed. Any other answer prevents mv from overwriting the target.

/usr/bin/mv

/usr/xpg4/bin/mv

The following operands are supported:

source

A path name of a file or directory to be moved.

target_file

A new path name for the file or directory being moved.

target_dir

A path name of an existing directory into which to move the input files.

See largefile(5) for the description of the behavior of mv when encountering files greater than or equal to 2 Gbyte ( 2³¹ bytes).

See environ(5) for descriptions of the following environment variables that affect the execution of mv: LC_CTYPE, LC_MESSAGES, and NLSPATH.

The following exit values are returned:

0

All input files were moved successfully.

>0

An error occurred.

See attributes(5) for descriptions of the following attributes:

/usr/bin/mv

/usr/xpg4/bin/mv

cp(1), cpio(1), ln(1), rm(1), setfacl(1), chmod(2), attributes(5), environ(5), fsattr(5), largefile(5), XPG4(5)

A -- permits the user to mark explicitly the end of any command line options, allowing mv to recognize filename arguments that begin with a -. As an aid to BSD migration, mv will accept - as a synonym for --. This migration aid may disappear in a future release.