You may want to use no-wait I/O with SNA IMF to do the following:
Overlap processing on the host by
using multiple SNA IMF devices.
Respond to host or local (HP 3000) terminal interrupts asynchronously.
You can overlap processing on the host during execution of
one program on the HP 3000 by using multiple HP devices. With no-wait
I/O, the program can issue a RECV3270 request for each device in use and then wait for
the first host response with IOWAIT.
You may want some of your applications to respond either to
a host interrupt or to a terminal local to the HP 3000. For example,
when Pass Thru, which uses SNA IMF intrinsics, issues a read to
the HP terminal, it follows the read with a call to RECV3270 and then a call to IOWAIT. IOWAIT delays Pass Thru processing until either the RECV3270 or the terminal read completes.
