Subject: Re: utmp file format change
To: Charles M. Hannum <root@ihack.net>
From: James Graham <greywolf@starwolf.com>
List: tech-userlevel
Date: 09/27/2001 08:35:02
Charles Hannum wrote:
# ab>
# ab> int f = open(NULL, O_RDWR|O_CREAT|O_UNLINK, 0);
# ab>
# ab> which would give me back something that had a link count of zero.
#
# Making this a standard feature is a *terrible* idea. If it wasn't
# politically infeasible, I would have made I/O to unlinked files fail
# years ago. This sort of hack makes it nearly impossible to analyze WTF
# is going on when something breaks.
How is it a "hack"? It'd be more of a hack to suddenly reclaim resources
on an unlinked file. The separation between the in-core metadata and the
on-disk metadata was, as far as I can tell, deliberately designed into
the OS. I/O to unlinked files was the initial form of IPC; even pipes
were on-disk buffers as opposed to in-core for the longest time.
ktrace/ktruss in the present day makes it much less nearly impossible
to analyze WTF is going on when something breaks (especially in the
verbosity provided by NetBSD -- I can't be as polite about Solaris).
--*greywolf;
--
NetBSD: For The Network Generation