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From: roderic@vicom.com (Roderic Taylor)
Newsgroups: comp.unix.wizards
Subject: Re: How do I implement asynchronous driver that works under sunview
Keywords: Sun, Sunview, device driver
Message-ID: <1990Jun29.202036.11409@vicom.com>
Date: 29 Jun 90 20:20:36 GMT
References: <1990Jun27.213349.5287@vicom.com>
Organization: Vicom Systems Inc., San Jose, CA
Lines: 16

[ In a recent message, I said I was having trouble with a Sunview ]
[ event handler reading input asynchronously from a driver I'd    ]
[ written.  I had implemented SIGIO for the driver, but assumed   ]
[ I needed to do it in a more standard manner that SunView can    ]
[ manipulate.                                                     ]

   As a number of people have pointed out to me, SunView does
not implement event handlers through signal catchers, but rather
through a select() command that blocks until input comes in on
any of the file descriptors the notifier expects input from.
My driver did not call selwakeup() in its interrupt routine (which
wakes up proceses blocked on select), and that was the problem.
Many thanks to all those who took the time to reply.


                                                     --Roderic T