Availability:C-language interface function
IOSTREAM * PL_acquire_stream(IOSTREAM
*s)Obtain ownership of s and return s. The
application must call PL_release_stream()
when done. Only one thread can own a stream and this call blocks if some
other thread owns the stream. This function may be called multiple times
by the same thread (recursive lock). Note that PL_get_stream()
also acquires ownership.