chown

The chown command (abbreviation for change owner) is used on Unix-like systems to change the owner of a file system object (files and directories). Unprivileged (regular) users who wish to change the group of a file that they own may use chgrp.

From the BSD man page for chown:

For obvious security reasons, the ownership of a file may only be altered by a super-user. Similarly, only a member of a group can change a file's group ID to that group.^[1]

Usage examples

These examples illustrate typical syntax and use. Modifying permissions requires you are either root or own a file. Changing owner requires root privilege.

• Change the owner of /var/run/httpd.pid to 'root' (the standard name for the Superuser).

 $ chown root /var/run/httpd.pid

• Change the owner of strace.log to 'rob' and the group identifier to 'developers'.

 $ chown rob:developers strace.log

• Change the owner of /tmp and /var/tmp to ‘nobody’ (not a good idea), and change the group of /tmp and /var/tmp to ‘nogroup’

 $ chown nobody:nogroup /tmp /var/tmp

• Change the group identifier of /home to 512 (regardless of whether a group name is associated with the identifier 512 or not).

 $ chown :512 /home

• Change the ownership of base to the user foouser and make it recursive (-R)

 $ chown -R foouser base

• Change the ownership to newuser and group to newgroup for all of the files and directories in current directory, and all subdirectories (recursively).

 $ chown -R newuser:newgroup .

• To verify that the owner or group has been changed, type

  ls -l
  

  to see who owns a file and what group it's part of (i.e. the 3rd and 4th columns respectively).

References

1. BSD Man page for chown, March 31, 1994

See also

• chgrp
• chmod
• takeown

External links

• chown – Commands & Utilities Reference, The Single UNIX® Specification, Issue 7 from The Open Group
• chown manual page
• The chown Command by The Linux Information Project (LINFO)