Test that we properly close off our input to the subprocess
   * such that it knows there's no tty connected. This is important
   * so that, if we use 'ssh', it won't try to prompt for a password
   * and block forever, for example.
Test that we properly close off our input to the subprocess
   * such that it knows there's no tty connected. This is important
   * so that, if we use 'ssh', it won't try to prompt for a password
   * and block forever, for example. | TestShellCommandFencer.java