Environment

jruby 1.7.25 (1.9.3p551) 2016-04-13 867cb81 on Java HotSpot(TM) 64-Bit Server VM 1.8.0_31-b13 +jit [Windows 7-amd64]

Expected Behavior

• Ruby should not print warnings related to tty when running on Windows

Actual Behavior

When I run JRuby on Jenkins, but invoked from a Cygwin shell, I get the annoying warning message

stty: standard input: Inappropriate ioctl for device

This does not happen when I run JRuby from a (Cygwin-) command line (interactively), or on Jenkins from a Windows command line.

I remember that there was a very similar error in jruby 1.7.23, where a stty warning was always shown when executing jruby from a Cygwin shell script, even with an interactive one. This error had been fixed in 1.7.24.

Running the script as a Jenkins job means that there is no console associated to the job. Perhaps the bugfix mentioned, did not pay attention to this possibility.

Thomas Enebo commented to this in the JRuby mailing list in the following way: "The gist of things is when you run via cygwin on Jenkins it is from a daemon and it has no tty associated with it. When we run stty you get this error. When you run from a cygwin windows it does have a tty so stty completes without issue."