sem_post - unlock a semaphore

       For an explanation of the terms used in this section, see attributes(7).
       ┌─────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                                                                   │ Attribute     │ Value   │
       ├─────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │ sem_post()                                                                  │ Thread safety │ MT-Safe │
       └─────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

sem_post()  increments  (unlocks) the semaphore pointed to by sem.  If the semaphore's value consequently
       becomes greater than zero, then another process or thread blocked in a sem_wait(3) call will be woken  up
       and proceed to lock the semaphore.

EINVALsem is not a valid semaphore.

       EOVERFLOW
              The maximum allowable value for a semaphore would be exceeded.

       See sem_wait(3) and shm_open(3).

       POSIX.1-2001.

       POSIX threads library (libpthread, -lpthread)

       sem_post - unlock a semaphore

sem_post() is async-signal-safe: it may be safely called within a signal handler.

sem_post()  returns 0 on success; on error, the value of the semaphore is left unchanged, -1 is returned,
       and errno is set to indicate the error.

sem_getvalue(3), sem_wait(3), sem_overview(7), signal-safety(7)

Linux man-pages 6.9.1                              2024-05-02                                        sem_post(3)

       POSIX.1-2008.

#include<semaphore.h>intsem_post(sem_t*sem);