On Mon, 2007-02-12 at 12:04 -0800, Michael Brailsford wrote: > bash-2.03$ sudo find /usr -name lockfile > bash-2.03$ uname -a > AIX <snip> 3 5 00C5227E4C00 > > Not so standard, methinks. AIX 5.3L has no such command.
I'll rephrase that. Any modern unix should have this command. :) Unless you happen to be using some old archaic unix. > > However, touch works well. Something like this has always worked for me. > > while [ -d /var/somelockfile ]; do sleep 1; done > touch /var/somelockfile > # do something > rm /var/somelockfile Sadly this will not work, at least if you goal is to synchronize multiple scripts running asynchronously. It would have worked in my case, but it's not a semaphore. Who wins when several processes make it past the while loop at about the same time? Michael > > > > > ----- Original Message ---- > From: Bart Whiteley <[EMAIL PROTECTED]> > To: Provo Linux Users Group Mailing List <[email protected]> > Sent: Monday, February 12, 2007 1:03:19 PM > Subject: Re: synchronizing concurrent shell scripts > > On 2/12/07, Michael L Torrie <[EMAIL PROTECTED]> wrote: > > > > On Mon, 2007-02-12 at 11:45 -0700, Michael L Torrie wrote: > > > I have a situation where shell scripts, executed asynchronously, need to > > > have a way to wait for each other when doing a load-intensive operation. > > > Do any of you have any methods for synchronizing the operation of > > > concurrent shell scripts? > > > > My bad. Google reveals that there's a nice standard unix > > command: /usr/bin/lockfile > > > > man lockfile reveals this is just what I'm looking for. > > > > > lockfile... cool. If you happen to be using bash, you can do the same thing > with a 'set -o noclobber' and avoid the overhead of forking an additional > process (lockfile). > http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_03_06.html#sect_03_06_02 > > /* > PLUG: http://plug.org, #utah on irc.freenode.net > Unsubscribe: http://plug.org/mailman/options/plug > Don't fear the penguin. > */ > > > > > /* > PLUG: http://plug.org, #utah on irc.freenode.net > Unsubscribe: http://plug.org/mailman/options/plug > Don't fear the penguin. > */ > /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
