haugj@pigs.UUCP (John F. Haugh II) (09/23/88)
In article <8349@bigtex.uucp> james@bigtex.UUCP (James Van Artsdalen) writes: >Older UUCPs did not use the (relatively new) capability of kill to >detect the existence of a process, and hence simply assumed that a >lock was "stale" if it was old enough. "Old enough" often meant an >hour or two. This scheme doesn't [ work ] terribly well. the kill (PID, 0) idiom has been in unix since 7th Edition days, at least. it is common to both BSD and USG unixii, so it can be used without worrying about portablity. uuclean should still be set to remove LCK.. files that are more than a few hours old so that LCK..<system> files will be deleted if they are abandoned. [ LCK..<device> files will be removed by uucico if need be ] -- =-=-=-=-=-=-=-The Beach Bum at The Big "D" Home for Wayward Hackers-=-=-=-=-=-= Very Long Address: John.F.Haugh@rpp386.dallas.tx.us Very Short Address: jfh@rpp386 "ANSI C: Just say no" -- Me
james@bigtex.uucp (James Van Artsdalen) (09/24/88)
In article <430@pigs.UUCP>, haugj@pigs.UUCP (John F. Haugh II) wrote: > uuclean should still be set to remove LCK.. files that are more than > a few hours old so that LCK..<system> files will be deleted if they > are abandoned. uuclean should *>NOT<* remove LCK files unless the locking process is no longer active. "a few hours" is certainly not long enough to ensure that the original process has gone away - I've had uucico sessions last upwards of eight hours (during news floods). If uuclean removes an active LCK and the remote's uuclean does likewise, you're quite likely to have a second set of uucico's start up a second session, resulting in duplicate mail or news and a probable ASSERT error once the two uucico's start removing each other's [CD]. files. -- James R. Van Artsdalen ...!uunet!utastro!bigtex!james "Live Free or Die" Phone: 512-346-2444 10926 Jollyville Rd #901 Austin TX 78759
davidsen@steinmetz.ge.com (William E. Davidsen Jr) (09/27/88)
In article <8422@bigtex.uucp> james@bigtex.UUCP (James Van Artsdalen) writes: | In article <430@pigs.UUCP>, haugj@pigs.UUCP (John F. Haugh II) wrote: | | > uuclean should still be set to remove LCK.. files that are more than | > a few hours old so that LCK..<system> files will be deleted if they | > are abandoned. | | uuclean should *>NOT<* remove LCK files unless the locking process is | no longer active. "a few hours" is certainly not long enough to | ensure that the original process has gone away - I've had uucico | sessions last upwards of eight hours (during news floods). As John says "if abandoned". I don't remember how or if uuclean checks, but the "unlock" program I posted some time ago does just what you say. I run it just before all scheduled executions of uucico, since I had a problem with an old version of uucico which ocasionally just "went away". -- bill davidsen (wedu@ge-crd.arpa) {uunet | philabs}!steinmetz!crdos1!davidsen "Stupidity, like virtue, is its own reward" -me