I am no expert on file locking but I don't think that's possible.

It is. 

$ touch lock

$ perl -M5.010 -MFcntl=LOCK_EX -e'
   open(my $fh, "<", "lock") or die $!;
   flock($fh, LOCK_EX) or die $!;
   say "ok";
'
ok

[download]

flock locks have nothing to do with reading and writing, and they prevent neither. They merely prevent locks from being obtained.

Seeking work! You can reach me at ikegami@adaelis.com

In reply to Re^2: singleton lock not reliable by ikegami
in thread singleton lock not reliable by pidloop

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