DosResetEventSem: Difference between revisions

Revision as of 12:20, 21 November 2016

Syntax

rc = DosResetEventSem( hevSemaphore, 
                       pulPostCount );

Parameters

HEV hevSemaphore (input): The handle of the semaphore to be reset.
PUL pulPostCount (output): The post count of the semaphore that was reset. This can not be set to NULL, it must be a valid pointer to ULONG.

Returns

APIRET rc

The following values can be returned

0	NO_ERROR	Semaphore released successfully
6	ERROR_INVALID_HANDLE	Error, The value in phevSemaphore does not point to a valid semaphore, The calling process must first have access to the semaphore in question
300	ERROR_ALREADY_RESET	Error, The semaphore is already reset, no posts have occurred since last reset

Include Info

#define INCL_DOSSEMAPHORES
#include <os2.h>

Usage Explanation

DosResetEventSem resets the post count of an event semaphore.

Gotchas

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

Sample Code

 
#define INCL_DOSSEMAPHORES
#include 

HEV  hevMySemaphore;     /* MySemaphore handle */
ULONG PostCount          /* storage for the post count of MySemaphore */

	/* access is gained to the semaphore in question */
	/* either by DosCreateEventSem ... */
	/* ... or by DosOpenEventSem */
	/* its handle is placed in hevMySemaphore */

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

	rc = DosResetEventSem(hevMySemaphore, &PostCount);

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