topic Re: semaphore in Operating System - HP-UX

semaphore

tarek_3 — Tue, 21 Jan 2003 06:35:06 GMT

sorry i send this message twice with in the wrong category,i hope this time ....
hi
i have a probleme with my c program.
when i kill my program the semaphore related still set. the program run as root
how can i know the correct ID to remove semaphore set related to my program.

Re: semaphore

Carlo Henrico_1 — Tue, 21 Jan 2003 07:05:00 GMT

Do a man on ipcs and ipcrm. ipcs shows what aemaphores are in use and ipcrm will clear them.

Good luck

Carlo

Re: semaphore

Ravi_8 — Tue, 21 Jan 2003 07:09:01 GMT

Hi,

$ipcs
list all IPC
to terminate ipc's kill wouldn't work

to kill semaphores
$ipcrm -s

Re: semaphore

Dietmar Konermann — Tue, 21 Jan 2003 07:59:36 GMT

This is the normal behaviour unless you set SEM_UNDO in your semaphore operations's sem_flg. Only in this case the kernel will perform the undo operation when the process exits. However, complete removal of the semaphore needs to be done explicitely using (signal driven) cleanup functions.

See man semop(2) for more details.

Best regards...
Dietmar.