Query: sem_close
OS: hpux
Section: 2
Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar
sem_close(2) System Calls Manual sem_close(2)NAMEsem_close - close a named POSIX semaphoreSYNOPSISDESCRIPTIONis used to close a named semaphore. A successful call to will do the following: Remove the process's descriptor for the semaphore refer- enced by the specified structure sem. Remove the semaphore referenced by the specified structure sem, if the semaphore is marked for removal by a call to and there are no other descriptors referencing this semaphore. When the process's descriptor for the semaphore referenced by sem is removed, subsequent use of this semaphore by this process will fail. Descriptors for named semaphores are also removed by processes on exit. Calling does not affect other processes referencing the same sema- phore. To use this function, link in the realtime library by specifying on the compiler or linker command line.EXAMPLESThe following call to will close a named semaphore referred to by sem by removing the process's descriptor to the semaphore and removing the semaphore if it is marked for removal by a previous and there are no descriptors referencing it.RETURN VALUEIf the semaphore was closed and the descriptors referencing it were removed, returns 0 to the caller. If the semaphore could not be closed, the call returns -1 and sets to indicate the error.ERRORSfails and does not perform the requested operation if the following condition is encountered: [EINVAL] The argument sem is not a valid named semaphore.WARNINGSA single call will make the semaphore unusable by the process no matter how many times that process had called for the same semaphore. Subsequent calls to by the same process for the same semaphore will result in an undefined behavior.SEE ALSOsem_init(2), sem_open(2), sem_unlink(2), <semaphore.h>.STANDARDS CONFORMANCEsem_close(2)
Related Man Pages |
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sem_open(2) - hpux |
sem_trywait(2) - hpux |
sem_trywait(3) - osf1 |
sem_wait(3) - osf1 |
sem_close(3rt) - sunos |
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