chown

- change file ownership

Synopsis

/usr/bin/chown

/usr/bin/chown [-fhR] owner[:group] file...

/usr/bin/chown -s [-fhR] ownersid[:groupsid] file...

/usr/bin/chown -R [-f] [-H | -L | -P] owner[:group] file...

/usr/bin/chown -s -R [-f] [-H | -L | -P] ownersid[:groupsid] file...

/usr/xpg4/bin/chown

/usr/xpg4/bin/chown [-fhR] owner[:group] file...

/usr/xpg4/bin/chown -s [-fhR] ownersid[:groupsid] file...

/usr/xpg4/bin/chown -R [-f] [-H | -L | -P] owner[:group] file...

/usr/xpg4/bin/chown -s -R [-f] [-H | -L | -P] ownersid[:groupsid] file...

Description

/usr/bin/chown and /usr/xpg4/bin/chown

The chown utility sets the user ID of the file named by each file to the user ID specified by owner, and, optionally, sets the group ID to that specified by group.

If chown is invoked by other than the super-user, the set-user-ID bit is cleared.

Only the owner of a file (or the super-user) can change the owner of that file.

The file system has a mountpoint option, rstchown, to restrict ownership changes. When this option is in effect the owner of the file is prevented from changing the owner ID of the file. Only the super-user can arbitrarily change owner IDs, whether or not this option is in effect.

chown changes the ownership of each file to owner. owner can be specified as either a user name or a numeric user id. The group ownership of each file can also be changed to group by appending :group to the user name.

Options

/usr/bin/chown and /usr/xpg4/bin/chown

The following options are supported:

-f

Force. Does not report errors.

-h

If the file is a symbolic link, this option changes the owner of the symbolic link. Without this option, the owner of the file referenced by the symbolic link is changed.

-H

If the file specified on the command line is a symbolic link referencing a file of type directory, this option changes the owner of the directory referenced by the symbolic link and all the files in the file hierarchy below it. If a symbolic link is encountered when traversing a file hierarchy, the owner of the target file is changed, but no recursion takes place.

-L

If the file is a symbolic link, this option changes the owner of the file referenced by the symbolic link. If the file specified on the command line, or encountered during the traversal of the file hierarchy, is a symbolic link referencing a file of type directory, then this option changes the owner of the directory referenced by the symbolic link and all files in the file hierarchy below it.

-P

If the file specified on the command line or encountered during the traversal of a file hierarchy is a symbolic link, this option changes the owner of the symbolic link. This option does not follow the symbolic link to any other part of the file hierarchy.

-s

The owner and/or group arguments are Windows SID strings. This option requires a file system that supports storing SIDs, such as ZFS.

Specifying more than one of the mutually-exclusive options -H, -L, or -P is not considered an error. The last option specified determines the behavior of chown.

/usr/bin/chown

The following options are supported:

-R

Recursive. chown descends through the directory, and any subdirectories, setting the specified ownership ID as it proceeds. When a symbolic link is encountered, the owner of the target file is changed, unless the -h or -P option is specified. However, no recursion takes place, unless the -H or -L option is specified.

/usr/xpg4/bin/chown

The following options are supported:

-R

Recursive. chown descends through the directory, and any subdirectories, setting the specified ownership ID as it proceeds. When a symbolic link is encountered, the owner of the target file is changed, unless the -h or -P option is specified. Unless the -H, -L, or -P option is specified, the -L option is used as the default mode.

Operands

The following operands are supported:

owner[:group]

A user ID and optional group ID to be assigned to file. The owner portion of this operand must be a user name from the user database or a numeric user ID. Either specifies a user ID to be given to each file named by file. If a numeric owner exists in the user database as a user name, the user ID number associated with that user name is used as the user ID. Similarly, if the group portion of this operand is present, it must be a group name from the group database or a numeric group ID. Either specifies a group ID to be given to each file. If a numeric group operand exists in the group database as a group name, the group ID number associated with that group name is used as the group ID.

file

A path name of a file whose user ID is to be modified.

Usage

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

Examples

Example 1 Changing Ownership of All Files in the Hierarchy

The following command changes ownership of all files in the hierarchy, including symbolic links, but not the targets of the links:

example% chown -R -h owner[:group] file...

Environment Variables

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

Exit Status

The following exit values are returned:

0

The utility executed successfully and all requested changes were made.

>0

An error occurred.

Files

/etc/passwd

System password file

Attributes

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

/usr/bin/chown

/usr/xpg4/bin/chown

See Also

chgrp(1), chmod(1), chown(2), fpathconf(2), passwd(4), system(4), attributes(5), environ(5), largefile(5), standards(5)

Notes

chown is CSI-enabled except for the owner and group names.