sem_wait
sem_wait
Wait on a semaphore.
Signature
Status sem_wait(
Capref sem )
Arguments
- sem - A
capref
specifying a capability for a semaphore.
Semantics
This call is used decrement the count of the semaphore sem. If the count
is positive prior to the call, the count is decremented and the operation
succeeds immediately. If the count is zero or negative prior to the call, the
count is decremented and the calling
locus
is blocked until another locus performs a
sem_signal
operation on sem. When it is awakened, the operation succeeds.
Status
See Also
Capref
Loci
sem_signal