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Building a CGI Script
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A CGI script is a dynamically-generated web page.  The content of the
page is produced not from a static text file, but rather from the
output of commands running on the web server.  The content of the web
page changes as the output of the commands change.

You can build a dynamic web page using Unix commands.  Here's how.

1) Create a public_html directory in your HOME directory on ACADAIX.
   Make sure it has read and execute permissions for everyone.

2) Put these four lines of text into the file public_html/who.cgi:
   The lines must start at the left margin.  No indenting!  (If you
   haven't learned any VI yet, use the method on the top of page 97 to
   create the who.cgi text file.)

       #!/bin/sh
       echo "Content-Type: text/plain"
       echo ""
       who

   Display the file to verify that it looks EXACTLY as above.

3) Turn on execute permissions (for you, group, and other) on the
   new file who.cgi file.
   
   Next, test the executable file at the shell prompt first:

     $ cd public_html
     $ ./who.cgi | more

   Verify that the first line of output is "Content-Type: text/plain".
   The second line must be blank.
   The rest of the output should be the output of "who".

   Fix any errors you find.

4) Enter a URL in this form into Netscape:

     http://acadaix/~abcd0001

   Replace abcd0001 with your acadaix userid.  If you get a permission
   denied error, add "x" permissions to your HOME directory to allow
   others to search it.  Make sure the public_html directory has both
   "r" *and* "x" permissions for everyone.

   You should now see the name of your who.cgi script.  Click on it
   to make the script execute.  If you get a permission denied error,
   fix the permissions to allow others to read and execute the file.

5) Modify the end of the script to include any other Unix commands you
   might know, e.g. date, echo, ls, write, etc.  Test the script from
   the shell prompt first, then finally try it from Netscape.

At present, you cannot access your ACADAIX web page from outside the
College because the ITS department doesn't allow anyone but ITS to run
web servers on campus.  The only web server you are permitted to
access from off-campus is on NETSRV.