Re: The 'users' gid: sync, games, and man
ma, 10-02-2003 kello 06:32, Graham Wilson kirjoitti:
> On Mon, Feb 10, 2003 at 01:00:09AM +0000, Colin Watson wrote:
> > On Sun, Feb 09, 2003 at 04:35:17PM -0600, Graham Wilson wrote:
> > > what do you mean it is used for running sync?
> > >
> > > $ ls -l /bin/sync
> > > -rwxr-xr-x 1 root root 9752 Feb 8 10:06 /bin/sync
> > $ grep sync /etc/passwd
> > sync:x:4:100:sync:/bin:/bin/sync
> sorry for my ignorance, but im still not following.
Unix systems have traditionally had a user called "sync" that has no
password and which runs /bin/sync on login (and then, obviously,
immediately exits). It was supposed to be useful when users noticed that
the computer was going to crash and let them tell the operating system
to flush all buffers to the disk (that's what /bin/sync does).
I'm not sure it's particularly useful anymore, however, and it might be
an ancient relic that is not worth keeping.