def popen3(cmd, bufsize=0, mode="t"):
    """Executes cmd as a sub-process. Returns the file objects (child_stdout, child_stdin, child_stderr)."""
    command = _get_str(cmd)
    i, o, e = os_popen.popen3(None, command, mode, bufsize)
    return o, i, e
Executes cmd as a sub-process. Returns the file objects (child_stdout, child_stdin, child_stderr).
lib/mlpatches/modules/popen2.py