Subject:    -5- Why do I get DGL errors when I try to run a GL program?
Date: 20 Feb 1994 00:00:01 EST

  - There may be a problem with the DISPLAY variable or Xwindows
    permissions. See the previous question.

  - You may be trying to display on a non-SGI machine which doesn't
    have GL/DGL. (Most don't, yet.) Presently the only way around this
    is to buy a third-party GL emulator for the non-SGI machine.

  - DGL may be disabled in /etc/services and/or /etc/inetd.conf. The
    former file should have a line reading

      sgi-dgl         5232/tcp

    and the latter should have a line reading

      sgi-dgl stream  tcp   nowait  root   /usr/etc/dgld  dgld -IM -tDGLTSOCKET

    If either is commented out, remove the comment.

  - You may be trying to display on a machine with a much older version
    of IRIX. Try another machine with a newer IRIX.

  An article in the Jan/Feb 1993 Pipeline describes the above in great
  detail.