Docs » Autodocs » exec.library » ReleaseSemaphore
ReleaseSemaphore -- make signal semaphore available to others
ReleaseSemaphore(signalSemaphore)
A0
void ReleaseSemaphore(struct SignalSemaphore *);
ReleaseSemaphore() is the inverse of ObtainSemaphore(). It makes
the semaphore lockable to other users. If tasks are waiting for
the semaphore and this this task is done with the semaphore then
the next waiting task is signalled.
Each ObtainSemaphore() call must be balanced by exactly one
ReleaseSemaphore() call. This is because there is a nesting count
maintained in the semaphore of the number of times that the current
task has locked the semaphore. The semaphore is not released to
other tasks until the number of releases matches the number of
obtains.
Needless to say, havoc breaks out if the task releases more times
than it has obtained.
signalSemaphore -- an initialized signal semaphore structure
In V39 and V40 Kickstart, there is an error condition that bumps
ss_NestCount twice, if multiple Procure() SemaphoreMessages and
a ObtainSemaphore() are pending for the same task.
This call is guaranteed to preserve all registers.
InitSemaphore(), ObtainSemaphore(), ObtainSemaphoreShared()
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