c - Structure of sem_t and implementation of semaphores -


in c programming language why need special sem_t type defining semaphore? couldn't been integer?how sem_t defined? how functions sem_post , sem_wait implemented? edit:an example implementation gnu c library great.

semaphores os kernel managed objects, sem_t os-specific, signal/wait calls since call os kernel.

usually, semaphores implemented unit count , queue waiting threads.


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