en:ibm:ifs:helpers:semwait

FSH_SEMWAIT

Purpose

This function allows an FSD to wait for an event. The event is signaled by a call to FSH_SEMCLEAR.

Calling Sequence

int far pascal FSH_SEMWAIT(pSem, cmsTimeout)
 
void far * pSem;
unsigned long cmsTimeout;

Where

pSem is the handle to the system semaphore or the long address of the ram semaphore.

cmsTimeout is the number of milliseconds to wait.

Returns

If no error is detected, a zero error code is returned. If an error is detected, one of the following error codes is returned:

  • ERROR_SEM_TIMEOUT – the time-out expired without gaining access to the semaphore.
  • ERROR_INTERRUPT – the current thread received a signal.
  • ERROR_PROTECTION_VIOLATION – the semaphore is inaccessible.

Remarks

The caller may return after the time-out period has expired without receiving an ERROR_SEM_TIMEOUT. Semaphore time-out values, therefore, should not be used for exact timing and sequence.

FSH_SEMWAIT may block.

Note: OS/2 does not validate input parameters. An FSD, therefore, should call FSH_PROBEBUF where appropriate.