In article <63f5d53a-2767-48f2-b7fa-fbfe93f63...@me.com>, Jason Thorpe <thor...@me.com> wrote: >As far as I can tell, POSIX has no language that covers this situation, >so Iâm tossing it out here for the hive mind... > >Is there ANY situation where, for a given pthread condition variable, >that using a different mutex as the interlock in two different calls to >pthread_cond_wait() would EVER be legitimate usage? I cannot come up >with any scenario in which this would be appropriate, but who knows what >some crazy applications might do. > >POSIX for whatever dumb reason allows pthread_cond_signal() / >pthread_cond_broadcast() without holding the interlock, but at least >thereâs explicit language about this in the spec (and thankfully the >language contains a mild finger-wag about it). But as I said, the spec >is silent on this particular question, and hopefully itâs because the >answer is âNO THAT IS A COMPLETELY STUPID THING TO DO AND ANY SELF >RESPECTING THREAD LIBRARY WILL IMMEDIATELY CAST YOUR APPLICATION INTO >THE NINTH CIRCLE OF HELL IF YOU TRY ITâ. > >What say you, smart people? > >Merci dâavance.
We should at least add language in our manual pages explaining that holding the mutex - while not required - is highly desired, and will make things work reliably. Currently I don't see anything mentioning the mutex in our man pages (the opengroup ones do mention it). christos
