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From: yozzo@larouch.UUCP (Ralph Yozzo)
Newsgroups: comp.os.os2
Subject: Re: Is there a way to peek ahead and see how many bytes are in the COM buffer?
Message-ID: <1989Dec25.025130.27715@larouch.uucp>
Date: 25 Dec 89 02:51:30 GMT
References: <1989Dec24.103004.26003@larouch.uucp>
Sender: news@larouch.uucp (Usenet News Program)
Organization: Larouch Headquarters
Lines: 20

From article <1989Dec24.103004.26003@larouch.uucp>, by yozzo@larouch.uucp (Ralph Yozzo):
> 
> Does anyone know of a way to peek ahead and see how many bytes are in 
> the COM1 buffer?
> The reason I ask is that I'd like to read as many bytes
> as possible from the COM port and I'd rather
> not ask for too much because the DosRead() will block.
> 
To answer my own question, there is a DosDevIOCtl() call that
gives the number of characters in the receive queue.

The call is documented in the I/O Subsystems and Device Drivers Volume 1
page 7-34 Category 1- Function 68H
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| Ralph E. Yozzo                     |                                       |
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