Synopsis
#include <sys/threads.h>
int condBroadcast(handle_t h);
int condSignal(handle_t h);
Status
Implemented
Conformance
Phoenix-RTOS specific
Description
These functions shall unblock threads blocked on a condition variable.
The condBroadcast() function shall unblock all threads currently blocked on the specified conditional variable h.
The condSignal() function shall unblock at least one of the threads that are blocked on the specified condition
variable h (if any threads are blocked on h).
If more than one thread is blocked on a condition variable, the scheduling policy shall determine the order in which threads are
unblocked. When each thread unblocked as a result of a condBroadcast() or condSignal() returns from
its call to condWait(), the thread shall own the mutex with which it called
condWait(). The thread(s) that are unblocked shall contend for
the mutex according to the scheduling policy (if applicable), and as if each had called mutexLock().
The condBroadcast() or condSignal() functions may be called by a thread whether or not it
currently owns the mutex that threads calling condWait() have associated with the condition variable
during their waits; however, if predictable scheduling behavior is required, then that mutex shall be locked by the thread calling
condBroadcast() or condSignal().
The condBroadcast() and condSignal() functions shall have no effect if there are no threads
currently blocked on cond.
The behavior is undefined if the value specified by the cond argument to condBroadcast() or
condSignal() does not refer to an initialized condition variable.
Return value
If successful, the condBroadcast() and condSignal() functions shall return zero; otherwise, an
error number shall be returned to indicate the error.
Errors
The condBroadcast() and condSignal() function may fail if:
-
-EINVAL- The value h does not refer to an initialised condition variable. -
-EINVAL- Parent process for h variable ceased to exist during function call
These functions shall not return an error code of -EINTR.
Tests
Untested
Known bugs
None