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From: bert@let.rug.nl (Bert Bos)
Newsgroups: comp.unix.programmer,comp.windows.x
Subject: Asynchronous input from several sources: how?
Keywords: X Windows events, pipe, non-blocking
Message-ID: <1487@gufalet.let.rug.nl>
Date: 10 Jan 91 15:39:27 GMT
Followup-To: poster
Organization: Faculty of Arts, Groningen University, The Netherlands
Lines: 19

I'm writing a program using X Windows that also needs to read input
coming in over a pipe. The incoming data is displayed in a window, but
while that happens, the program has to check for events (expose,
button press, etc.)

My current solution is to simply poll both sources of input (using
non-blocking read and XPending) but this seems rather wasteful of
processor time. Is there a way to wait for something to arrive on
either channel? Would such a solution indeed be more efficient?

(I'm using X11R3, no widgets, and HP-UX; programming is done in C)

Please e-mail.

-- 
  "Always remember, however, that there's     Bert Bos (bert@let.rug.nl)
   usually a simpler and better way to do     Alfa-informatica
   something than the first way that pops     RijksUniversiteit Groningen
   into your head." (D.E. Knuth, TeXbook)     Groningen, The Netherlands