On Wed, 11 Feb 1998 13:41:25 +0200  Jukka Marin wrote:

> Is this a bug or a feature?

Feature.

If you are the owner of a file, only the owner permissions count.

If you are /not/ the owner, but are a member of the group of the file,
only the group permissions count.

If you are /not/ the owner and /don't/ belong to the group then the
other (world) permisions are used.

The Linux behaviour is a bug.  (Caveat: you *could* get this behviour
on a SysV single-group-at-a-time machine that had newgrp.  I don't
believe Linux would use that model.)

Anyone got a POSIX standard handy for chapter and verse?

Giles