commandline session
$> 1 $flock 1 $ls 1 $echo 1 > 1 $cat 1 1 $ls -l total 4 -rw-r--r-- 1 jeffrin jeffrin 2 Aug 11 18:24 1 $flock -n 1 $echo 1 > 1 $ls -l total 4 -rw-r--r-- 1 jeffrin jeffrin 2 Aug 11 18:29 1 $1 /var/loc local/ lock/ $1> /var/lock/mylock $cat 1 1 $rm 1 $ls $ls -l /var/lock/mylock -rw-r--r-- 1 jeffrin jeffrin 0 Aug 11 18:30 /var/lock/mylock $rm /var/lock/mylock $ls $1> /var/lock/mylock $cat /var/lock/mylock $cat /var/lock/mylock $flock /var/lock/mylock ls $ls $cat /var/lock/mylock $