Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!jhunix!andy
From: andy@jhunix.HCF.JHU.EDU (Andy S Poling)
Newsgroups: comp.mail.elm
Subject: Re: Will ELM ever use lockf()?
Summary: be careful...
Keywords: lockf, flock, fcntl, mailbox locking
Message-ID: <7857@jhunix.HCF.JHU.EDU>
Date: 29 Mar 91 17:31:51 GMT
References: <1991Mar25.193741.12360@coplex.uucp> <5062@lgnp1.ls.com>
Followup-To: comp.mail.elm
Organization: The Johns Hopkins University - HCF
Lines: 28

In article <5062@lgnp1.ls.com> phil@ls.com (Phil Eschallier) writes:
>In article <1991Mar25.193741.12360@coplex.uucp> dean@coplex.uucp (Dean Brooks) writes:
[...]
>>   If elm were to support "lockf()" all my problems would be gone.  Are
>>there any hopes in the future of this being included in the elm source?
>>
>
>	correct me if i am wrong but this seems like a trivial problem --
>	there are several places to get code that emulates flock() using
>	lockf().  
[..]
>	then -- couldn't you just tell elm's configuration that you will
>	use flock() and link in this procedure ??

Be careful - lockf requires that a file be opened for both read and write.
Really should use the fcntl(F_SETLK), etc. (which is what most lockf()s use
anyway...).

IMHO Elm should offer lockf() as one of the locking options - that's what
our SYSV local mailer uses.  It ain't gonna do much good to lock the mailbox
if the mailer and Elm are usin' different locking methods...

-Andy
--
Andy Poling                              Internet: andy@gollum.hcf.jhu.edu
UNIX Systems Programmer                  Bitnet: ANDY@JHUNIX
Homewood Academic Computing              Voice: (301)338-8096    
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