Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!hsdndev!think.com!zaphod.mps.ohio-state.edu!mips!wdl1.wdl.loral.com!wdl50!mdm
From: mdm@wdl50.wdl.loral.com (Mike D Marchionna)
Newsgroups: comp.sys.next
Subject: XtAddInput analog in NeXT Step
Summary: Is an analog to XtAddInput available in NeXT Step
Keywords: X windows, NeXT Step, programming
Message-ID: <1991Mar1.174526.17075@wdl1.wdl.loral.com>
Date: 1 Mar 91 17:45:26 GMT
Sender: news@wdl1.wdl.loral.com
Organization: LORAL Western Development Labs
Lines: 24


	Hey gang.  Here is something unusual for this group, a programming
question. :-)  I have recently been toying with the idea of porting some X
window code to NeXT step.  Most of the code would seem to have similar or
equivalent functionality to certain NeXT Step objects except for one aspect.
In X there is a function called XtAddInput that allows the caller to specify a
UNIX file descriptor to monitor.  XtAddInput will invoke a specified callback
routine whenever there is data to read on the indicated file descriptor.
Basically XtAddInput generates a pseudo window event that your program can
choose to respond as you see fit.  I don't know if any such functionality
exists under Next Step.  In NeXT Stepese I guess what I what I would need is a
function that could be called without blocking, and would send a specified
message to a specified object whenever the indicated file descriptor has
information to read.  One approach I had in mind was to start a Mach thread
that performed a blocking read and then sent an Objective C message to NXApp
or some such object that read and processed the data and then restarted the
the thread for the next read.  Is there any way to implement such a function,
or is one already available.  Many thanks for any information this group is
kind enough to provide.
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|El-Rayo-X-----||--##--%%--@@----->| Brain and brain!  What is brain!     |
|El-Rayo-X-----||--##--%%--@@----->|       --Star Trek (Spock's Brain)    |
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