$ for q in 1 2 3 4 ; do perl 807067.pl & done
Fri Nov 13 17:21:04 2009: 20079's flock attempt starts
Fri Nov 13 17:21:04 2009: 20079's flock obtained
Fri Nov 13 17:21:04 2009: 20080's flock attempt starts
Fri Nov 13 17:21:04 2009: 20082's flock attempt starts
Fri Nov 13 17:21:04 2009: 20081's flock attempt starts
Fri Nov 13 17:21:09 2009: 20079 ends
Fri Nov 13 17:21:09 2009: 20081's flock obtained
Fri Nov 13 17:21:14 2009: 20081 ends
Fri Nov 13 17:21:14 2009: 20082's flock obtained
Fri Nov 13 17:21:19 2009: 20082 ends
Fri Nov 13 17:21:19 2009: 20080's flock obtained
Fri Nov 13 17:21:24 2009: 20080 ends