NAME
    FindSemaphore -- find a given system signal semaphore
SYNOPSIS
    signalSemaphore = FindSemaphore(name)
    D0                              A1
    struct signalsemaphore *findsemaphore(strptr);
FUNCTION
    This function will search the system signal semaphore list for a
    semaphore with the given name.  The first semaphore matching this
    name will be returned.
    This function does not arbitrate for access to the semaphore list,
    surround the call with a forbid()/permit() pair.
INPUT
    name - name of the semaphore to find
RESULT
    semaphore - a pointer to the signal semaphore, or zero if not
                found.