Subj : mutex and process termination
To   : comp.programming.threads
From : Christoph Bartoschek
Date : Fri Apr 01 2005 10:46 am

Hi,

what happens when a process holding mutexes dies? I'm speaking in terms of
pthread mutexes.

Are the mutex ressources cleaned up by the kernel as for example open file
descriptors? Are some kernel structures left used which are limited and can
eventually get exhausted?

I wonder whether a faulty programm, which locks a mutex and dies immediately
after that, can force me to reboot the machine, if it is executed several
million times.

Right now I'm thinking that the kernel cleans everything up, but in Unix
Network Programming Volume 2, Page 174 one can read:

When a mutex is shared between processes, there is always a chance that the
process can terminate (perhaps involuntarily) while holding the mutex lock.
There is no way to have the system automatically release held locks upon
process termination. We will see that read-write locks and Posix semaphores
share this property.

Is there a difference with mutexes which are shared between processes and
normal mutexes? 


Greets,
Christoph Bartoschek

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