Ох уж эти sysv-семафоры: $ ipcs -s -i 426007 Semaphore Array semid=426007 ... semnum value ncount zcount pid 0 0 0 0 580473 $ stat /proc/580473 stat: cannot statx '/proc/580473': No such file or directory $ stat /proc/*/task/580473 stat: cannot statx '/proc/*/task/580473': No such file or directory