Change the ownership of files and directories (POSIX)
chown [-hRv] owner[:group] file...
Deprecated:
chown [-hRv] owner[.group] file...
QNX Neutrino
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
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.
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 user.group 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 my.name and a group tech, you could do a chown my.name myfile or chown my.name:tech myfile, but not chown my.name.tech myfile.