STREAMS Programming Guide

qwait

A module that uses perimeters and must wait in its open or close procedure for a message from another STREAMS module has to wait outside the perimeters; otherwise, the message would never be allowed to enter its put and service procedures. This is accomplished by using the qwait(9F) interface. See qwriter(9F) man page for an example. For information about signal reception during a close, see close Routine