coreutils: Access permission tests
16.3.2 Access permission tests
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These options test for particular access permissions.
‘-g FILE’
True if FILE exists and has its set-group-ID bit set.
‘-k FILE’
True if FILE exists and has its “sticky” bit set.
‘-r FILE’
True if FILE exists and the user has read access.
‘-u FILE’
True if FILE exists and has its set-user-ID bit set.
‘-w FILE’
True if FILE exists and the user has write access.
‘-x FILE’
True if FILE exists and the user has execute access (or search
permission, if it is a directory).
‘-O FILE’
True if FILE exists and is owned by the current effective user ID.
‘-G FILE’
True if FILE exists and is owned by the current effective group ID.