Re: eternal 'ReadIntervalTimeOut' com port

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#15549

From: Remy Lebeau (TeamB)
Date: Tue, 24 Jun 2003 21:49

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"david" <dmarquezl@hotmail.com> wrote in message
news:3ef8bbd6@newsgroups.borland.com...

> I'm trying to use the com port, but when I read this buffer and there are
> not data, the handle don`t  return the control to the next code line.

Its not supposed to.  You're reading the port synchronously and you never
set the timeouts for the port, thus it is just going to sit there until data
is available.  You should be using overlapped I/O for the reading.  Have a
look at the OVERLAPPED structure and the GetOverlappedResult() function.

>   if( hCom == INVALID_HANDLE_VALUE )
>     return false;
>   else
>     return true;

You're never going to reach the rest of your code because you are returning
too soon.  Thus you never get a chance to set the timeouts.  Didn't the
compiler warn you about "unreachable code"?  Get rid of the second 'return'
statement.


Gambit

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From: "Remy Lebeau \(TeamB\)" <gambit47@yahoo.com>
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Subject: Re: eternal 'ReadIntervalTimeOut' com port
Date: Tue, 24 Jun 2003 14:49:33 -0700
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