multithreading - Do any mutex implementations allow locking from one thread and unlocking in another -


in discussion elsewhere has proposed there may platforms on mutex unlocked thread other locked it.

i'm unconvinced, experience limited platforms never allowed; there platforms allow it?

if there are, how 1 possibly utilise such facility? if can no longer assume mutex remains locked between lock , unlock steps seems me defeat point. there scenarios must done , can done safely care?

strictly speaking, no there isn't shared mutex between threads this. defeat purpose of mutex. if it's want, can use semaphore(1). semaphores allow non-acquiring threads release acquired count.


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