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Date: Fri, 6 Jan 2006 12:33:42 +0800
From: steven woody <narkewoody AT gmail DOT com>
To: Eric Blake <ericblake AT comcast DOT net>
Subject: Re: cat /dev/ttyS?
Cc: cygwin AT cygwin DOT com
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On 1/6/06, Eric Blake <ericblake AT comcast DOT net> wrote:
>
> >
> > 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.

thanks. dd works!

--
woody


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