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DosReleaseMutexSem

[ Syntax | Params | Returns | Include | Usage | Structs | Gotchas | Code | Also ]

Syntax

 rc = DosReleaseMutexSem( hmtxSemaphore );

Parameters
HMTX hmtxSemaphore (input)
The handle of the semaphore to be released.

Returns
APIRET rc
The following values can be returned
0NO_ERRORSemaphore released successfully
6ERROR_INVALID_HANDLEError, The value in phmtxSemaphore does not point to a valid semaphore, The calling process must first have access to the semaphore in question
288ERROR_NOT_OWNERError, The calling process does not currently own the semaphore

Include Info

 #define INCL_DOSSEMAPHORES
#include <os2.h>

Usage Explanation

 DosReleaseMutexSem releases ownership of mutex semaphore. It decrements, by one (1), the usage count of the mutex semaphore refered 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.

Relevant Structures

Gotchas

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

Sample Code

 #define INCL_DOSSEMAPHORES #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

 DosCloseMutexSem, DosCreateMutexSem, DosOpenMutexSem, DosQueryMutexSem, DosRequestMutexSem

Author

Joe Phillips - jaiger@eng2.uconn.edu

Additions

Last modified May 29/1996
Please send all errors, comments, and suggestions to: timur@vnet.ibm.com

The OS/2 API Project

DosReleaseMutexSem