Hi mightyMrJawz,

I could have up to 50 servers trying to determine if the file exists

To be honest, it really sounds like you need a database instead. Update: Note this quote from the File::NFSLock documentation: "Locks are not necessarily obtained on a first come first serve basis. Not only does this not seem fair to new processes trying to obtain a lock, but it may cause a process starvation condition on heavily locked files."

changed the code from "LOCK_EX" to "LOCK_NB"

AFAIK LOCK_NB is an option that is needed in addition to either LOCK_EX or LOCH_SH (Update: see also flock). See the example code at the top of File::NFSLock (I trimmed it down slightly):

use File::NFSLock;
use Fcntl qw(LOCK_EX LOCK_NB);
my $file = "somefile";
if (my $lock = new File::NFSLock {
    file      => $file,
    lock_type => LOCK_EX|LOCK_NB,
    blocking_timeout   => 10,      # 10 sec
    stale_lock_timeout => 30 * 60, # 30 min
}) {
    open(FILE, "+<$file") || die $!;
    # or open it any way you like
    # ...
    $lock->unlock();
}else{
    die "I couldn't lock the file [$File::NFSLock::errstr]";
}

[download]

Instead of dieing, you would let your code continue.

BTW, there seems to be something wrong with the <code> tags in your post. Perhaps you could edit your node to fix that.

Hope this helps,
-- Hauke D

In reply to Re: NFSLock - Continue in code if another server already has lock on file (updated) by haukex
in thread NFSLock - Continue in code if another server already has lock on file by mightyMrJawz

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