If you just want a simple incrementing counter, one way to do this is to use the size of the file as the counter, rather than its contents. You don't need locking to do this: 

my $filename = '/path/to/file';

# Increment the counter (atomically, so no locking required)
open(FILE, ">> $filename") or warn "Missed a count";
print FILE '.'    # Ouput one (arbitrary) byte
close FILE;

# What is the counter set to?
my $countval = -s $filename || 0;

[download]

The disadvantage of this technique is that it uses one byte of disk space for each count.

In reply to Re: Re: Flock Feedback by tomhukins
in thread Flock Feedback by footpad

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