J. Blustein

Web-centric Computing

Some Example Code

SSI Test Page

This page looks different on

• torch.cs.dal.ca (which you should use), and
• users.cs.dal.ca

What works (and what doesn't)

1. <!--#echo var="DATE_LOCAL" -->
   Tuesday, 28-Oct-2025 08:02:59 ADT
2. <!--#echo var="document_name" -->
   test1.shtml
3. <!--#exec cmd="/usr/bin/echo exec works" -->
   [an error occurred while processing this directive]
4. Include virtual works on torch (see below)

Sometimes small differences matter...

1. <!--#echo var="DATE_LOCAL" -->
   Tuesday, 28-Oct-2025 08:02:59 ADT
2. <!-- #echo var="DATE_LOCAL" -->
   
   Because of the extra space in the second example, the directive is not recognized

A whole lot of testing goin' on

1. Date & Time

   1. <!--#echo var="DATE_LOCAL" -->
      Tuesday, 28-Oct-2025 08:02:59 ADT
   2. <!--#echo var="Date_GMT" -->
      Tuesday, 28-Oct-2025 11:02:59 GMT

2. About this document

   1. <!--#echo var="DOCUMENT_NAME" -->
      test1.shtml
   2. <!--#echo var="DOCUMENT_URI" -->
      /~jamie/CS4173/Materials/examples/SSI/test1.shtml
   3. <!--#echo var="last_modified" -->
      Wednesday, 05-Jan-2005 17:55:49 AST

3. About this server

   1. <!--#echo var="server_name" -->
      web.cs.dal.ca
   2. <!--#echo var="server_software" -->
      Apache

4. About the user/browser

   1. <!--# echo var="HTTP_USER_AGENT" -->
      [an error occurred while processing this directive]
   2. <!--# echo var="GATEWAY_INTERFACE" -->
      [an error occurred while processing this directive]
   3. <!--#echo var="remote_addr" -->
      216.73.216.11

5. Files on the server (executables and data files)

   1. <!--#exec cmd="/usr/bin/echo exec works" -->
      [an error occurred while processing this directive]
   2. <!--#exec cmd="/usr/bin/id" -->
      [an error occurred while processing this directive]
   3. <!--#exec cmd="/usr/bin/cat /etc/passwd" -->
      [an error occurred while processing this directive]

6. If

        <pre>
         <!--#if expr="apple=orange" -->
          If is not working
         <!--#else -->
          If *is* working
         <!--#endif -->
        </pre>
        

         [an error occurred while processing this directive]
          If is not working
         
        

7. CGI executables within SSI

   1. CGI directive

                 <!--#exec cgi="/~maxwell/cgi-bin/test-cgi.cgi" -->
               

                 [an error occurred while processing this directive]
               

   2. Include virtual directive

                 <pre>
      
                   <!--#include virtual="/~maxwell/cgi-bin/test-cgi.cgi" -->
      
                 </pre>
                

                  CGI/1.0 test script report:
      
      argc is 0. argv is .
      
      SERVER_SOFTWARE = Apache
      SERVER_NAME = web.cs.dal.ca
      GATEWAY_INTERFACE = CGI/1.1
      SERVER_PROTOCOL = INCLUDED
      SERVER_PORT = 443
      REQUEST_METHOD = GET
      HTTP_ACCEPT = */*
      PATH_INFO = 
      PATH_TRANSLATED = 
      SCRIPT_NAME = /~maxwell/cgi-bin/test-cgi.cgi
      QUERY_STRING = 
      REMOTE_HOST =
      REMOTE_ADDR = 216.73.216.11
      REMOTE_USER =
      AUTH_TYPE =
      CONTENT_TYPE =
      CONTENT_LENGTH =
      
      Id : 
      uid=5002(maxwell) gid=1035(csstaff) groups=1035(csstaff),1032(fcsfile),1033(cstech),1036(ember),1043(deepsense),1051(fcsaio),1088(cshelp),1091(officestaffdrive),1092(deansofficedrive),5012(dstech),6010(malnis),17997(awxadmins) context=system_u:system_r:httpd_suexec_t:s0
      
      
      Environment: 
      SERVER_SIGNATURE=
      SSL_TLS_SNI=web.cs.dal.ca
      UNIQUE_ID=aQCi469HCeP-FZ1X2r3k6AAAGBM
      HTTP_USER_AGENT=Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
      SERVER_PORT=443
      HTTP_HOST=web.cs.dal.ca
      DOCUMENT_ARGS=
      DOCUMENT_ROOT=/local/data/web.cs.dal.ca/web/
      SCRIPT_FILENAME=/users/webhome/maxwell/cgi-bin/test-cgi.cgi
      HTTPS=on
      REQUEST_URI=/~jamie/CS4173/Materials/examples/SSI/test1.shtml
      USER_NAME=
      SCRIPT_NAME=/~maxwell/cgi-bin/test-cgi.cgi
      REMOTE_PORT=17585
      PATH=/usr/local/bin:/usr/bin:/bin
      CONTEXT_PREFIX=/~maxwell
      PWD=/users/webhome/maxwell/cgi-bin
      SERVER_ADMIN=cshelp@cs.dal.ca
      REQUEST_SCHEME=https
      DATE_GMT=
      HTTP_ACCEPT=*/*
      DOCUMENT_URI=/~jamie/CS4173/Materials/examples/SSI/test1.shtml
      DATE_LOCAL=
      REMOTE_ADDR=216.73.216.11
      SHLVL=1
      SERVER_NAME=web.cs.dal.ca
      LAST_MODIFIED=
      DOCUMENT_NAME=test1.shtml
      SERVER_SOFTWARE=Apache
      QUERY_STRING=
      SERVER_ADDR=129.173.22.11
      GATEWAY_INTERFACE=CGI/1.1
      SERVER_PROTOCOL=INCLUDED
      HTTP_ACCEPT_ENCODING=gzip, br, zstd, deflate
      REQUEST_METHOD=GET
      CONTEXT_DOCUMENT_ROOT=/users/webhome/maxwell
      _=/usr/bin/env
      
      
      Stdin: 
      
      
      ------------ DONE ------------
      
                

Important Notes

• filename ends with .shtml not .html
• must not be in or beneath your cgi-bin directory
• must run on http://torch.cs.dal.ca not http://www.cs.dal.ca
• note the difference between echo var and exec
• spaces matter for some directives
• case might matter for some directives
• You must experiment with the server that you will be using
• See the Apache HTTP Server mod_include documentation for detailed specifications

http://www.cs.dal.ca/~jamie/course/CS/4173/examples/SSI/test1.shtml

Version:

23 October 2001

Based on

ssitest.shtml from Chris Maxwell

Prof:

J. Blustein <jamie@cs.dal.ca>