Re: Bug#497514: coreutils: chmod, chown, and chgrp change ctime even when no change was necessary

[Paul Eggert]

Erik Rossen <address@hidden> writes:

> And, if one wants to be REALLY pedantic, it looks like the file node is
> supposed to be changed each time.  For example, here is an extract:

As I read the spec, chown and chgrp are explicitly required to make
the equivalent of a chown() call, which in turn is required to change
the ctime.  However, chmod is not required to make the equivalent of a
chmod() call, and there is no requirement in the 'chmod' spec that it
change the ctime.  So POSIX allows the optimization for the 'chmod'
command, but not for the 'chown' and 'chgrp' commands.