If you're prepared to wait indefinitely for the lock, then your scripts should run in the correct order just with your simple model. 
#!/usr/bin/perl -w

use strict;
use Fcntl ':flock'; # import LOCK_* constants

my $lockfile_path = "./lockfile";

open(LOCKFILE, ">$lockfile_path") or die "Can't open $lockfile_path: $
+!";
flock(LOCKFILE,LOCK_EX);
print "got lock @ARGV\n";
sleep(10);
print "finished sleeping @ARGV\n";
flock(LOCKFILE,LOCK_UN);

[download]
If you run multiple instances of this script like so... 
./test.pl 1 &
./test.pl 2 &
./test.pl 3 &
./test.pl 4 &

[download]
...you'll see them running in the correct order. As you point out, this does break if the flock fails and you need to get back in the queue though.

In reply to Re: Locking/unlocking program execution using a queue by reasonablekeith
in thread Locking/unlocking program execution using a queue by RazorbladeBidet

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