SYS$WFLOR (OpenVMS) SYS$WFLOR (OpenVMS)
NAME
semop - perform semaphore operations
SYS$WFLOR - Wait for logical OR of event flags
EXPLAINATION
Although there is no directly corresponding function to the OpenVMS
SYS$WFLOR system service, it is possible, though the use of a conven‐
tion in handling a semaphore set, to wait for the logical OR of event
flags by using a guard semaphore. One process waits on the guard sema‐
phore, when the guard semaphore is down, the process continues and
checks the semaphore values of the semaphore set it wishes to do a log‐
ical or on. This also requires that cooperating processes set the
guard semaphore down after setting values in the semaphore set. It may
be possible to use shared memory and semaphores to emulate this aspect
of event flags more efficiently.
RELATED INFORMATION
Digital UNIX Functions:
semop(2), semget(2), semctl(2), shmget(2) delim off
SYS$WFLOR (OpenVMS)
