For what it's worth, I'm not running xterm (I don't even have XWindows installed), and I'm seeing most of the same symptoms.

Here's the script I use to launch a cygwin shell, cygwin.bat:
@echo off

C:
chdir C:\cygwin\bin

bash --login -i
And I get similar results as Weiqi:
False
False
False

[<type 'java.io.BufferedInputStream'>, <type 'java.io.FilterInputStream'>, <type 'java.io.InputStream'>, <type 'java.io.Closeable'>, <type 'java.lang.Object'>, <type 'object'>]
Don't know if that helps at all.

-moss

Nicholas Riley wrote:
In article <025F6281-1F0E-4969-B53E-AB127449E892@underboss.org>,
 Philip Jenvey <pjenvey@underboss.org> wrote:

  
Nick, any idea why isatty fails here? Incorporating Weiqi's changes is  
no problem, but having to workaround isatty failing with JYTHON_OPTS="- 
i" sucks.
    

It fails because Weiqi's using a Cygwin *xterm*, rather than Cygwin 
inside cmd.exe.  You can see the differences here:

   <http://web.sabi.net/temp/isatty.png>

Note that CPython fails worse than Jython when run in a Cygwin xterm (or 
rxvt in my case); jython -i without Weiqi's changes also doesn't work 
correctly, but python -i does.
  

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Moss Prescott
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