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From: klee@wsl.dec.com (Ken Lee)
Newsgroups: comp.windows.x
Subject: Re: Help! What is the magic of the sleep() statement?
Message-ID: <1991Jan9.153215@wsl.dec.com>
Date: 9 Jan 91 23:32:15 GMT
References: <1991Jan9.150326.6248@warwick.ac.uk>
Sender: news@pa.dec.com (News)
Reply-To: klee@wsl.dec.com
Organization: DEC Western Software Laboratory
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In article <1991Jan9.150326.6248@warwick.ac.uk>, csuyk@warwick.ac.uk (FUNG Wai Wa) writes:
|> The following few statements attempt to create a window and draw a line
|> with some strings. I found that the sleep(1) statement is very crucial
|> for its success.

This is one of the most common X beginners problems.  X is
asynchronous, so there is no guarantee that your window is mapped
before you start drawing.  Instead, you should only draw on a window
after receiving an expose event.  Most people use the X Toolkit, which
worries about this for you.

-- 
Ken Lee
DEC Western Software Laboratory, Palo Alto, Calif.
Internet: klee@wsl.dec.com
uucp: uunet!decwrl!klee