isatty(stdio) on cygwin/xterm/rxvt

[Sam Steingold]

when running under bash or cmd in a console, cygwin returns
        isatty(0) ==> true
        isatty(1) ==> true
when running under bash in an xterm (or rxvt) under cygwin X, I get
        isatty(0) ==> false
        isatty(1) ==> false

how do I check that I am running in a cygwin xterm or rxvt
(as opposed to, say, stdio being redirected to/from a file)?

thanks.

-- 
Sam Steingold (http://www.podval.org/~sds) running w2k
<http://www.camera.org> <http://www.iris.org.il> <http://www.memri.org/>
<http://www.mideasttruth.com/> <http://www.palestine-central.com/links.html>
Linux: Telling Microsoft where to go since 1991.