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From: reeves@dvinci (Malcolm Reeves)
Newsgroups: comp.lang.pascal
Subject: Re: How Can I empty COM1 port in TP?
Message-ID: <1990Sep4.050722.29241@herald.usask.ca>
Date: 4 Sep 90 05:07:22 GMT
References: <34499@unix.cis.pitt.edu>
Sender: news@herald.usask.ca (USENET News System)
Reply-To: reeves@dvinci
Organization: University of Saskatchewan
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From article <34499@unix.cis.pitt.edu>, by cncst@unix.cis.pitt.edu (Christophe N. Christoff):
> 
> The title says it all.  How can I empty COM1 port in TP?
> How can I tell how many characters are there in COM1?

Read them one at a time until there are none.
This isn't meant to be a facetious reply - to answer your question I need to
know how you are reading from COM1. You should have a buffer somewhere with
a pointer to tell you how full it is. I flush the COM buffer by setting the
pointer to position zero but there are lot's of ways to write a serial port
handler. There's a PD unit called Asynch I think which does a reasonable job.
Hope this is of some use.