Re: Process-Shared Mutex (futex) - What is it good for ?

[Peter Wächtler]

Vladimir Zidar wrote:
>  Nice to have everything as POSIX says, but how could process-shared
> mutex be usefull ? Imagine two processes useing one mutex to lock shared
> memory area. One process locks, and then dies (for example, it goes
> sigSEGV way). Second process could wait for ages (untill reboot ?) and
> it won't get lock() on that mutex ever. Wouldn't it be more usefull to
> have automatic mutex cleanup after process death ? Just make a cleanup,
> and mark it as 'damaged', so other processes will eventualy get error
> saying that something went wrong.
> 
> 

Look at kernel/futex.c in 2.5 tree.
I vote for killing the "dangling" process - like it's done in IRIX.