Chgrp

chgrp, short for change group, is a shell command for changing the group associated with a Unix-based file system file – including special files such as directories. Changing the group of a file is restricted to a super-user (such as via sudo) or to the file's owning user if the user is in the specified group.

chgrp

Example usage of chgrp command to change the files' groups
Developer(s)	AT&T Bell Laboratories
Initial release	May 1975; 50 years ago (1975-05)
Written in	Plan 9: C
Operating system	Unix, Unix-like, Plan 9, Inferno, IBM i
Platform	Cross-platform
Type	Command
License	Plan 9: MIT License

A file has access permissions for the owning user, a group and for others. Changing the group for a file changes access to it based on users' group memberships.

History

The chgrp command was originally developed as part of the Unix operating system by AT&T Bell Laboratories. It is available in most Unix-like systems, Plan 9, Inferno and IBM i.^[1]

The version of chgrp bundled in GNU coreutils was written by David MacKenzie.^[2]

Use

Generally, the syntax can be described as:

chgrp [options] group files

• group specifies the group with which the files should be associated; may be either a symbolic name or an identifier
• files specifies one or more files, which may be the result of a glob expression like *.conf

Options:

• -R Recurse through directories
• -v Verbose output: log the name of each file changed
• -f Force or forge ahead even if an error occurs

Examples

The following demonstrates changing the group of files matching *.conf to staff – provided the user owns the files (is gbeeker) and is a member of staff. The change will allow members of the group staff to modify the files since the group-class permissions (read/write) will apply; not the others-class permissions (read only).

$ ls -l *.conf
-rw-rw-r--   1 gbeeker  wheel          3545 Nov 04 2011  prog.conf
-rw-rw-r--   1 gbeeker  wheel          3545 Nov 04 2011  prox.conf
$ chgrp staff *.conf
$ ls -l *.conf
-rw-rw-r--   1 gbeeker  staff          3545 Nov 04 2011  prog.conf
-rw-rw-r--   1 gbeeker  staff          3545 Nov 04 2011  prox.conf

See also

• chmod – Shell command for changing access permissions of a file
• chown – Shell command for changing the owner of a file
• Group identifier (Unix) – Unix/POSIX system account group number; numeric value used to represent a specific groupPages displaying short descriptions of redirect targets
• List of POSIX commands