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you're not supposed to open, and then lock your lock/semaphore file...

As someone unfamiliar with flock semantics, could you explain how your comments sits with the example given in the docs for flock:

use Fcntl ':flock'; # import LOCK_* constants sub lock { flock(MBOX,LOCK_EX); # and, in case someone appended # while we were waiting... seek(MBOX, 0, 2); } sub unlock { flock(MBOX,LOCK_UN); } open(MBOX, ">>/usr/spool/mail/$ENV{'USER'}") or die "Can't open mailbox: $!"; lock(); print MBOX $msg,"\n\n"; unlock();

and with flock taking a filehandle? Doesn't that mean I have to open it before I lock it?

I'm blissfully unaware or "how you're supposed to do it", using different mechanisms for this purpose, but I find the documentation decidedly unclear. Care to explain it?


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In reply to Re: Re: Mysterious Disapperance of file contents by BrowserUk
in thread Mysterious Disapperance of file contents by Gorby

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