unix - POSIX Threads: are pthreads_cond_wait() and others systemcalls? -

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POSIS defines several routines for standard thread synchronization, such as by mutuxes and conditional variables.

My question is now: are these (like pthreads_cond_init (), pthreads_mutex_init (), pthreads_mutex_lock () ... and so on) system calls or just library calls? I know that they are included through "pthread.h", but are they ultimately the result of a system call and therefore apply to the operating system kernel?

Do not want any thread by taking a lock.

Similarly, sending a condition signal is only costly when someone is waiting for it.

So I assume that your answer It is that pthread functions are library calls which are occasionally in the result of the system call.


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