Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!wuarchive!uwm.edu!bionet!agate!ucbvax!osf.org!dbrooks
From: dbrooks@osf.org
Newsgroups: comp.windows.x.motif
Subject: Re: Capturing Stdout/stderr to scrolling window
Message-ID: <9103062327.AA02012@penge.osf.org>
Date: 6 Mar 91 23:27:38 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Distribution: inet
Organization: The Internet
Lines: 32

mrabin@ADS.COM (Marla Rabin) writes:
|> In main, before realizing and main-looping I have the line:
|> 	XtAddInput(fileno(stdin), XtInputReadMask, get_from_input, mainText);
|> 
|> where get_from_input is:
|> 
|> void
|> get_from_input(w, fid, id)
|>      Widget      w;
|>      int         *fid;
|>      XtInputId   *id;
|> {
|>   char  buf[BUFSIZ];
|>   int nbytes, i;
|> 
|>   extern void printToMain();
|> 
|>   fprintf(stderr, "in get\n");
|>   nbytes = read(*fid, buf, BUFSIZ);
			      ^^^^^^

Assuming the writer hasn't closed the pipe, this will block until
enough data is shoved across.  You'll have to do whatever SunOS offers
to perform a nonblocking read.

(Anyway, that's what occurred to me straight away.  I haven't looked
too closely at the mess of dup and close calls...)

-- 
David Brooks				dbrooks@osf.org
Systems Engineering, OSF		uunet!osf.org!dbrooks
"It's not easy, but it is simple."