Date: Wed, 13 Jan 1999 11:41:55 +0200 (IST) From: Eli Zaretskii X-Sender: eliz AT is To: dhensley AT my-dejanews DOT com cc: djgpp AT delorie DOT com Subject: Re: How to open COM port in DJGPP? In-Reply-To: <77g71i$d34$1@nnrp2.dejanews.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Reply-To: djgpp AT delorie DOT com On Tue, 12 Jan 1999 dhensley AT my-dejanews DOT com wrote: > if I set the COM port attributes through the Control Panel, does DOS (and > DJGPP) inherit those properties, or does DJGPP set some (other) arbitrary > attributes? DJGPP doesn't change any settings inside the call to `open'. So whatever properties you have set should be inherited, unless NT has its own views about what DOS programs should see. You will have to check. > > The filesystem extensions feature is described in the library > > reference; type "info libc alpha 'File System'" from the DOS prompt > > (the quotes around File System are important!). > > Will this work under NT? The filesystem extensions will work on any platform, since this is a machinery that's entirely internal to DJGPP; the low-level library calls are intercepted by your handlers *before* they are seen by the OS. What you need to establish is this: will NT allow you to change the settings of the COM port from within your handlers? If not, then DJGPP is not your solution, because the handler will be called, but will be unable to do its job. It might help if you described what settings does the program you are porting change (with the calls to termios functions). Then it can be estimated how hard would it be to achieve that on an NT. In general, NT is a very hard platform for such a low-level programming. It might be a good idea to switch to another OS.