Can we tell if a command is being run by a process or not, by looking at the flock lock file alone?

Is util-linux's flock implemented based on flock() in Linux C API? Can we tell if a command is being run by a process or not, by looking at the lock file alone? I found that when a command guarded by flock finishes running, there seems no change to the lock file. Here is when it is running and after it finishes running: $ ls -l ../sleep.flock.file -rw-rw-r-- 1 t t 0 Oct 30 14:01 ../sleep.flock.file $ ls -l ../sleep.flock.file -rw-rw-r-- 1 t t 0 Oct 30 14:01 ../sleep.flock.file Thanks.