Wakes one thread waiting on a given condition variable.
A condition variable
A generalized boolean
wakes exactly one thread waiting on the condition variable
. In most uses of condition variables, the caller should be holding the lock that the waiter used when calling condition-variable-wait for this condition variable, but this is not required.
The return value
is non-nil if a process was signalled, or
if there were no processes waiting.
LispWorks User Guide and Reference Manual - 22 Dec 2009