NAME
    UnLock -- Unlock a directory or file
SYNOPSIS
    UnLock( lock )
            D1
    void UnLock(BPTR)
FUNCTION
    The filing system lock (obtained from lock(), duplock(), or
    createdir()) is removed and deallocated.
INPUTS
    lock - BCPL pointer to a lock
NOTE
    passing zero to UnLock() is harmless
SEE ALSO
    lock(), duplock(), parentoffh(), duplockfromfh()