command not found, then you do not have the
directory containing the ef command in your PATH environment variable.
Either edit your shell startup file to fix this, or type the full path
name of the "ef" command.
If you experience other problems please contact Laplacian Optics Inc.
The ef command is actually a shell script which starts the required program. If you wish you may make a private copy of this script and modify it to your own preferences.