ACC Programmer's Reference Guide

292 Chapter4
ZCOM C I/F Library Routines
ZSET_RCVR (3X)
receiver of the incoming messages. Use of this feature does not require
that a p rimary receiver be defined. For every terminal, each receiver
mode (except mode ZcOUTB_MLTPLX) allows a maximum of
ZcMAX_SHARED_RCVRS (64) program Z LUs to be set wi th action
ZcADD_SHARED.
An application program can indicate that it no longer wishes to receive
messages by issuing a zset_rcvr() call with the same parameters as those
specified in the original zset_rcvr() request, and setting the action
parameter to ZcDEL_PRIMARY or ZcDEL_SHARED.
The libraries libzcom_c.a and libpthread.a must be linked into thecalling
program by giving the options “-lzcom_c -lpthread” to cc(1) or ld(1).
Threads
Considerations
This routine may be called from a multi-threaded application using the
POSIX (1003.1c) kernel threads API package. This routine has the
following characteristics when called by a multi-threaded application:
cancellation point Thread cancellation can occur when a thread calls this
routine.
async-cancel unsafe The calling thread’s cancelability type must be
PTHREAD_CANCEL_DEFERRED if cancellation is
enabled.
async-signal unsafe It cannot be called from a signal handler.
fork unsafe It cannot be called by a child process after fork(2) but
before exec(2).