sem_destroy(3)

1sem_destroy(3)             Library Functions Manual             sem_destroy(3)
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NAME

6       sem_destroy - destroy an unnamed semaphore
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LIBRARY

9       POSIX threads library (libpthread, -lpthread)
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SYNOPSIS

12       #include <semaphore.h>
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14       int sem_destroy(sem_t *sem);
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DESCRIPTION

17       sem_destroy()  destroys the unnamed semaphore at the address pointed to
18       by sem.
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20       Only a semaphore that has been initialized by sem_init(3) should be de‐
21       stroyed using sem_destroy().
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23       Destroying  a  semaphore  that other processes or threads are currently
24       blocked on (in sem_wait(3)) produces undefined behavior.
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26       Using a semaphore that has been destroyed produces  undefined  results,
27       until the semaphore has been reinitialized using sem_init(3).
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RETURN VALUE

30       sem_destroy() returns 0 on success; on error, -1 is returned, and errno
31       is set to indicate the error.
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ERRORS

34       EINVAL sem is not a valid semaphore.
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ATTRIBUTES

37       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
38       tributes(7).
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40       ┌────────────────────────────────────────────┬───────────────┬─────────┐
41       │Interface                                   │ Attribute     │ Value   │
42       ├────────────────────────────────────────────┼───────────────┼─────────┤
43       │sem_destroy()                               │ Thread safety │ MT-Safe │
44       └────────────────────────────────────────────┴───────────────┴─────────┘
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STANDARDS

47       POSIX.1-2008.
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HISTORY

50       POSIX.1-2001.
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NOTES

53       An  unnamed semaphore should be destroyed with sem_destroy() before the
54       memory in which it is located is deallocated.  Failure to do  this  can
55       result in resource leaks on some implementations.
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