HP X.25/9000 Programmer's Guide

86 Chapter5
Receiving and Transmitting Out-of-band Information
Transmitting Out-of-band Events
To send an INTERRUPT packet, issue the send() system call with the
MSG_OOB flag set. If blocking I/O is being used, the application process
remains blocked until the INTERRUPT CONFIRMATION packet is
received. If nonblocking I/O is being used, the confirmation is received as
an out-of-band event ( 00B_VC_INTERRUPT_CONF ). See Chapter 4 ,
“Sending and Receiving Data,” for a description of how to send interrupt
data.
NOTE CCITT 1980 X.25 networks and equipment only support one byte of
interrupt data. If your X.25 interface is configured in the x25init(1M)
network type file as 1980 version and you attempt to send more than 1
byte of interrupt data, an EMSGSIZE error will be returned. If the
network provider does not support more than 1 byte of interrupt data
and you try to send more, the circuit will be reset. The network type file
is described in your X.25/9000 User’s Guide.
36960-90061.bk Page 86 Friday, November 10, 2000 3:42 PM