pol_sem

Outline

Acquire semaphore resource (polling).

C format

 ER      pol_sem ( ID semid );


Assembly format

 MOV     A, #semid
 CALL    !!_pol_sem


Parameter(s)

I/O

Parameter

Description

I

 ID      semid;
ID number of the semaphore from which resource is acquired.



Explanation

This service call acquires a resource from the semaphore specified by parameter semid (subtracts 0x1 from the semaphore counter).

If a resource could not be acquired from the target semaphore (semaphore counter is set to 0x0) when this service call is issued, the counter manipulation processing is not performed but "E_TMOUT" is returned.

Return value

Macro

Value

Description

E_OK

0

Normal completion.

E_TMOUT

-50

Polling failure.