Making Your Web Page Interactive with CGI TLN Technology Committee February 16, 1999

What is CGI? “A method used by www pages to communicate with programs run on the web server.” Glossary of Internet Terms

Finding Scripts §Matt’s Script Archive l worldwidemart.com/scripts §CGI Resource Index l §Web Scripts l awsd.com/scripts/

Downloading § Once you’ve found the script you want, download it and all the associated readme and html files. § Be sure to download in ascii text mode. l If available, save individual files instead of.zip file. This is the easiest way to ensure that the files are saved in ascii format. l If you must use the.zip file, open files in word after unzipping them to save them in ascii format.

Recognizing Ascii Format

Customizing Scripts

§ The first line of the.pl script must read: #!/usr/bin/perl NOT #!/usr/local/bin/perl § Change script name to “name.cgi” The.pl tag is not recognized on the server. Only scripts with the.cgi tag will run properly.

Customizing Scripts §The absolute path should be structured as follows: /mnt/web/guide/worldwidemart/scripts/ /home/lvcc/lvcc/www/cgi-bin/ § The url path to the designated file is the full path:

Uploading Files

Creating the CGI Directory and Uploading Files  The CGI-BIN Directory l Working in your FTP software: Open your www directory Create a new folder at the host within the www directory. Name the folder cgi-bin § Uploading Files l Working in your FTP software: Upload.cgi files to cgi-bin directory Upload.htm files to the regular www directory

Setting Permissions CHMOD

Changing Read/Write/Execute Access for CGI Files § Permission settings for each associated file depends upon the action of the script. § The readme file will usually tell you which permissions to assign to each file.

Chmod in Linux/Unix drwxr-xr-x 2 lvcc users 1024 Jan 15 10:02 cgi-bin -rw-r--r-- 1 lvcc users 1213 Jul momdad.htm -rw-r--r-- 1 lvcc users 6520 Jul money.jpg -rw-rw-rw- 1 lvcc users 2968 Jan 7 19:15 mypet.htm -rw-r--r-- 1 lvcc users 1942 Jun mypetadd.htm -rw-r--r-- 1 lvcc users 394 Aug 5 09:54 folks02.gif -rwxr-xr-x 1 lvcc users May formmail.cgi -rwxr-xr-x 1 lvcc users Jun mypet.cgi -rwxr-xr-x 1 lvcc users Jan pineknob.cgi § Www Long List of Directory § Cgi-bin Long List of Directory

Changing Read/Write/Execute Access for CGI Files chmod u=rwx,g=rx,o=rx form.cgi

CHMOD by Numbers Readme files will often use numbers to designate chmod settings. First digit = u Second digit = g Third digit = o 4 (r) + 2 (w) + 1 (x) = 7 4 (r) + 1 (x) = 5 chmod u=rwx,g=rx,o=rx form.cgi and chmod 755 form.cgi result in the same action.

Running The Script

Testing and Troubleshooting  Scripts must be uploaded and permissions changed before they can be tested.  Usually, a minor adjustment will correct script error messages. l Incorrect directory information or a misplaced slash will prevent a script from running.

Common Error Messages

The Form Mail Script In Action