Updated: April 19, 2023

Change the ownership of files and directories (POSIX)


chown [-hRv] owner[:group] file...


chown [-hRv] owner[.group] file...

Runs on:

QNX Neutrino


Modify the symbolic link instead of the referenced file.
Recursively change ownership of files. For each file operand that names a directory, chown changes the user ID of that directory and of all files in the file hierarchy below it.
Verbose. Display to stdout the operations which are being performed.
A username from the user database, or a numeric userid. The chown utility changes the owner of each file to the user ID of the specified owner.
A group name from the user database, or a numeric group ID. The chown utility changes the group of each file to the group ID of the specified group.
The pathname of a file whose ownership is to be modified.


The chown utility sets each file's owner and group to the user and group IDs specified by the owner and group operands.


Change the owner of file data to user 27:

chown 27 data

Change the owner of the file data to dtdodge:

chown dtdodge data

Change the owner of the file subfile to dtdodge and set the group of the file to techies:

chown dtdodge:techies subfile

Exit status:

The utility executed successfully and all requested changes were made.
An error occurred.


If you invoke chown with the -R option, and chown attempts but fails to change the owner or group of a particular file in a specified file hierarchy, it continues to process the remaining files in the hierarchy. The chown utility can fail to change the user or group of a file if you don't have appropriate permissions.

Note: In QNX Neutrino, the _PC_CHOWN_RESTRICTED flag is enforced, therefore you must be root to use chown unless you are changing ownership to yourself. Normal users can't give a file away to another user by changing the file ownership.

For compatibility with some other implementations of chown, a deprecated syntax allows a period (.) to be used instead of a colon (:) to separate user and group (e.g., user:group and are both allowed). However, be aware that if a userid contains a period, it may be specified either alone or in conjunction with a group using :, but may not be used in conjunction with a group using .. For instance, if there was a userid and a group tech, you could do a chown myfile or chown myfile, but not chown myfile.