Xref: utzoo comp.periphs:755 comp.unix.questions:5569
Path: utzoo!utgpu!water!watmath!clyde!burl!codas!mtune!mtgzz!avr
From: avr@mtgzz.UUCP (XMRP50000[jcm]-a.v.reed)
Newsgroups: comp.periphs,comp.unix.questions
Subject: Re: Unix Interrupts
Summary: Yes, but please follow the UNIX design philosophy when you do it.
Message-ID: <3617@mtgzz.UUCP>
Date: 15 Feb 88 19:08:15 GMT
References: <3102@cup.portal.com>
Organization: AT&T, Middletown NJ
Lines: 22

In article <3102@cup.portal.com>, Chuck_SirVAX_Staatse@cup.portal.com writes:
> Does anyone know if UNIX supports a "Connect to Interrupt" facillity
> similar to VMS or RSX. Failing an "Out of the Box" solution, has
> anyone cobbled something together? Target system is a 68000 VME based
> system.  Any takers?

UNIX provides a facility called "signals". Signals may be sent by
processes, open device files, or by the kernel. Most interrupts are used
within device drivers, but it is trivially simple to write a device
driver which will send the appropriate signal, to processes that have
opened it, when device receives an interrupt. Once the driver is
installed, you open its device file to connect to the interrupt, and you
close it to disconnect. You may use any signal - its your system - but
it is good programming practice to restrict yourself to standard signal
semantics:
		01	Hardware termination (hangup)
		02	Catchable interrupt
		03	Quit and dump core
		09	Kill absolutely and immediately (no cleanup!)
		16	User defined signal 1
		17	User defined signal 2
						Adam Reed (mtgzz!avr)