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From: ericblake AT comcast DOT net (Eric Blake)
To: steven woody <narkewoody AT gmail DOT com>, cygwin AT cygwin DOT com
Subject: Re: cat /dev/ttyS?
Date: Fri, 06 Jan 2006 04:02:35 +0000
Message-Id: <010620060402.4634.43BDEBDB000607880000121A22007507840A050E040D0C079D0A@comcast.net>
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> 
> oh, i found the 'cat /dev/ttyS1' really outputs, but it has a very
> *big* delay that leads me thought it does not response.   is the
> output buffered?  what do i do? thanks!

Yes, cat with no options calls read(), which typically uses buffers.  Try
cat -u to get unbuffered output.  Or there are other programs,
such as dd, which are better suited with options to tweak to get
unbuffered output.

--
Eric Blake
volunteer cygwin coreutils maintainer


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