From my understanding, flock is truely a syscall to the OS you are running the application on. So, in *nix, for example, if you man flock, you will get the manual for this specific function call.

One thing I've always done, therefore avoiding any direct system calls, is create a 'lock file'. Creating a simple file, where nothing is allowed to do 'anything' until the file is removed.

For example: 
sleep( 0.001 ) while ( -r '.lock' );

# You made it here, the file is gone

[download]
Naturally, it's always easy to say something like this, however you may be stuck with using flock. In that case, I would research the man pages of the OS you are running to find out the exact behavior of the syscall you're using.

---hA||ta----
print map{$_.' '}grep{/\w+/}@{[reverse(qw{Perl Code})]} or die while ( 'trying' );

In reply to Re: How to make sure that non-Perl programs will respect Perl's file locking? by wazzuteke
in thread How to make sure that non-Perl programs will respect Perl's file locking? by glasswalk3r

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