Visual C++ apps in a "telnet" window

Ian Collins
Sun Dec 12 17:39:00 GMT 1999

(Message used to be Visual C++ apps in a bash window)
Thanks for the reply, Earnie.

Replacing tty with notty in CYGWIN variable did the trick for the bash
However, it doesn't work for a telnet window started from inetd.
Any ideas?

Ian Collins.


Does your CYGWIN environment variable contain "tty"?  If so, this is
likely the reason you can't get it to work.  Either remove tty or use
the notty


--- Ian Collins <> wrote:
> I am trying to get an application that was compiled/linked under
> C++ to work in a bash window.
> The application requires that i/o be performed in "raw" mode, (i.e.,
> using ioctl, isatty, etc calls).
> When the application is run in an NT cmd window (dos prompt!), it runs

> fine.
> When run in a bash shell, isatty returns 0 (not in a terminal), and
> ioctl calls return
> "Invalid Arguments".
> Does anyone know how to make this work?
> I have a Console Application created with Visual C++, and want to run
> in
> a bash window.
> When the application is run (see code below), printf works fine, but
> isatty(fileno(stdin)) returns 0 (no terminal attached). Also any ioctl

> calls return a failure
> Is there any way to do this??
> //
> // Example code...
> //
> #include "stdafx.h"
> #include <stdio.h>
> #include <io.h>
> int main(int argc, char* argv[])
> {
> int i;
> i = _isatty(_fileno(stdin));
> printf("isatty returned: %d\n", i);
> return 0;
> }
> I also tried creating the same application using the MKS NutCracker
> suite
> (that application had ioctl) calls.
> This application also fails (and the ioctl calls failed with "Invalid
> Argument").
> (A gut feeling - would compiling bash using VC++ solve the problem -
> gulp!!).
> Regards,
> Ian Collins
> System Manager

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