Path: utzoo!attcan!uunet!husc6!cs.utexas.edu!sun-barr!texsun!texbell!sugar!ficc!morrison
From: morrison@ficc.uu.net (Brad Morrison)
Newsgroups: comp.unix.xenix
Subject: Re: Xenix Help ? MapChan : Shell Layers : Backup : File Locking
Summary: Try LK_NBLCK
Message-ID: <4453@ficc.uu.net>
Date: 8 Jun 89 12:54:11 GMT
References: <1169@cheops.eecs.unsw.oz> <724@mitisft.Convergent.COM>
Organization: {xe,u}nix Support
Lines: 16

In article <724@mitisft.Convergent.COM>, dold@mitisft.Convergent.COM (Clarence Dold) writes:
> in article <1169@cheops.eecs.unsw.oz>, ashley@cheops.eecs.unsw.oz (Ashley M. Aitken) says:
> > File "Locking":
> > 
> > I would like to lock a file while someone is editing it . . .

> A wrapper in this sense would open the target with a lock, then invoke
> the editor of choice via exec.  If you have an exclusive lock, and a mandatory
> locking file system, then someone else starting a vi would pause,
> waiting for the lock to be released.

Unless you try to lock without blocking; you can return immediately and
check errno for the EACCESS error.
-- 
    Grep me no patterns and     | Brad Morrison             (713) 274-5449
    I'll tell you no lines.     | uunet!ficc!morrison morrison@ficc.uu.net