def cmd_syst(args):
    """Show operating system type of server system.

           No read access required.

           Replying to this command is of questionable utility,
           because this server does not behave in a predictable way
           w.r.t. the output of the LIST command.  We emulate Unix ls
           output, but on win32 the pathname can contain drive
           information at the front Currently, the combination of
           ensuring that os.sep == '/' and removing the leading slash
           when necessary seems to work.  [cd'ing to another drive
           also works]

           This is how wuftpd responds, and is probably the most
           expected.  The main purpose of this reply is so that the
           client knows to expect Unix ls-style LIST output.

           one disadvantage to this is that some client programs
           assume they can pass args to /bin/ls.  a few typical
           responses:

           215 UNIX Type: L8 (wuftpd)
           215 Windows_NT version 3.51
           215 VMS MultiNet V3.3
           500 'SYST': command not understood. (SVR4)
        """
