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DosReleaseMutexSem releases ownership of mutex semaphore.


DosReleaseMutexSem( hmtxSemaphore );


 HMTX hmtxSemaphore (input)

The handle of the semaphore to be released.


The following values can be returned
0 NO_ERROR Semaphore released successfully
6 ERROR_INVALID_HANDLE Error, The value in phmtxSemaphore does not point to a valid semaphore, The calling process must first have access to the semaphore in question
288 ERROR_NOT_OWNER Error, The calling process does not currently own the semaphore

Usage Explanation

It decrements, by one (1), the usage count of the mutex semaphore referred to by hmtxSemaphore. If the usage count for the mutex semaphore goes to zero (0), ownership of the semaphore will be passed on to another thread that has been blocked for requesting it.

The process calling DosReleaseMutexSem must first obtain access to the semaphore in question or ERROR_INVALID_HANDLE will be returned.

Sample Code

#include <os2.h>

HMTX  hmtxMySemaphore;     /* MySemaphore handle */

	/* access is gained to the semaphore in question */
	/* either by DosCreateMutexSem ... */
	/* ... or by DosOpenMutexSem */
	/* its handle is placed in hmtxMySemaphore */

	/* process becomes owner of semaphore */
	/* by way of successful call to DosRequestMutexSem */

	rc = DosReleaseMutexSem(hmtxMySemaphore);

	if (rc != 0)
	  /* We got an error to take care of. */

See Also