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Newsgroups: comp.unix.bsd.freebsd.misc Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.rmit.EDU.AU!news.unimelb.EDU.AU!munnari.OZ.AU!spool.mu.edu!olivea!quack!quack.kfu.com!nsayer From: nsayer@quack.kfu.com (Nick Sayer) Subject: Re: MFS - Why? Message-ID: <nrOhw02@quack.kfu.com> Sender: news@quack.kfu.com (0000-News(0000)) Organization: The Duck Pond public unix, +1 408 249 9630, log in as guest. References: <AEn4jRr0u3@qsar.chem.msu.su> <npX7tgO@quack.kfu.com> <4po5am$6hc@news.zipnet.net> <Dt536J.MEK@info.elvisti.kiev.ua> <4q82lv$bs@anorak.coverform.lan> Date: Wed, 19 Jun 1996 20:45:15 UTC Lines: 32 The traditional reasoning goes like this: In the begining there was /tmp/ and /usr/tmp/. The point behind the two separate ones was that /tmp/ was cleaned out at reboot time, and /var/tmp/ was not. So if you needed a temp file to survive a reboot (like a vi session file), you put it in /usr/tmp/, but if you were going to create temp files that a reboot would cause you to _FORGET_ to remove (as is the case when you do something like mktemp() or in the shell you made a temp filename containing $$), you put them in /tmp/. When the dickless (diskless) client was invented, they moved all of the stuff that was in /usr/ at the time that needed to be writable on a per-client basis to a new place called /var/. So /usr/spool now became /var/spool. /usr/tmp/ became /var/tmp/. All of the old places in /usr/ were left behind only as symlinks. This way /usr/ was read-mostly (you could even mount it read only if you never built a kernel) on the clients and had no per-client localizations. You had one copy of /usr for the whole group and one root partition and swap file per client. That's where /var/tmp/ came from. It is what once was /usr/tmp/ before the invention of the DL client. /usr/tmp/ and /tmp/ existed because they had different treatment during a reboot. It is sensible to keep /var/tmp/ and /tmp/ separate so they can be treated differently. It is also sensible to keep the symlink going from /usr/tmp/ to /var/tmp/. -- Nick Sayer <nsayer@quack.kfu.com> | Anita Hill then, Paula Jones now. N6QQQ @ N0ARY.#NORCAL.CA.USA.NOAM | +1 408 249 9630, log in as 'guest' | What goes around, comes around. URL: http://www.kfu.com/~nsayer/ |