How to Make a Fill Out Form

Like Bellow's Henderson the Rain King, there is a little voice in my head that chants without ceasing, "I want I want I want". I saw a form and I wanted one. I wanted a bunch. I want forms that can be used with my students: for site navigation, anonymous comments, searching my site. I want forms that can be a playground of collaborative creation. I want to make forms that I can sell to to earn money and buy food!

I. What you Need to Know and Do Before You Begin

1. Am I allowed to run CGI on our site?

2. At some sites you must place your CGI scripts in a specially named directory. Sometimes directory must be above your web page directory and sometimes it can be inside your web directory. Again, your system administrator will specify. Usually this cgi directory is named cgi-bin, but it may have other names.

3. CGI scripts usually have to have a specific extension to the filename. Sometimes that extension is .pl for Perl scripts and sometimes .cgi is the file extension. And sometimes either is fine. You can try one or the other to see if it works, or ask your system administrator.

4. You will need to know both the URL of the web page referencing the CGI script and the absolute pathname to the script. Want to know more about file permissions, directories and paths? This [archived at the Wayback Machine - 2009] UNIX handout may help.

5. If you are using Perl scripts, you need to specify the path to the Perl interpreter. Scripts written in Perl require an interpreter to execute. Most system administrators follow a convention in placing the Perl interpreter. You can ask your system administrator for the path, or, if you have a shell account you can enter the following command at the UNIX prompt to get the path.
   whereis perl

6. If the results of the form are to be mailed to you then you'll need to know the path to your sendmail program. You can use the same whereis command: whereis sendmail

7. File permissions, along with directory paths are the most common problems with setting up CGI scripts. If you have a shell account, you can set the file permissions from the UNIX prompt. If you don't have access to a shell account you can set file permissions using an FTP program such as WS_FTP [link removed - 2009]. The UNIX handout will give you more information about file permissions.

II Required Files

1. The web page which contains the form. The HTML form tag includes many attributes to format various input fields, short answer, long answer, and radio buttons and check boxes for multiple choice. desired result. The NCSA Mosaic Guide to Fill-Out Forms [link removed - 2009] includes a set of links to examples of forms. You can learn a lot about making forms and web pages in general by viewing the source code of web pages. Viewing the source code allows you see the actual HTML of the page. In Netscape click on the View menu and select "Document Source". A new window will appear which will contain the HTML source code.

2. The CGI script that is executed when the form is submitted. This script takes the data entered in the form's fields and, depending on what kind of script you use, emails the results to you, and/or compiles a database and/or posts the data results to a new web page.

3. You need a web page to open after the form is submitted. Generally this page acknowledges receipt of the submitted information (i.e., "Thanks for your input!").

4. You may need a web page to report errors to the person completing the form. In the case of my test, if a student forgets to enter her name, I need a web page to remind her to go back and enter her name. If the form you are using doesn't require specific information to be included, you can omit this web page.

Creating a Query Form with AlienForm

The AlienForm page [link removed - 2009] includes excellent instructions for downloading and configuring the script and accompanying files.

1. Acquire the CGI script and template files from AlienForm [link removed - 2009]. This link takes you to the actual section of the page for downloading the script and the 5 related files: alienform.txt, form.txt, mail.txt, reply.txt, success.txt, error.txt

2. Rename the file alienform.txt to alienform.cgi or alienform.pl as necessary for your site. Edit the file to make the changes called for on the AlienForm web page. You will need to know:

   a. The path to your Perl interpreter

   Most system administrators follow a tradition of placing the Perl interpreter in the path /usr/bin/perl. If you have a shell account you can check the location of the Perl interpreter with the command: whereis perl, and the response will be the path statement. You can ask your system administrator for this information if you don't have shell access (i.e., access to the UNIX prompt).

   b. The path to your sendmail program

   Like the Perl interpreter, the sendmail program is generally available in the path /usr/sbin/sendmail, and you can check this location with the same command used for Perl: whereis sendmail.

   c. The path to your template files

   These template files come with AlienForm and include a file to report errors, a file to format the data to be mailed to you and a file to format a web page to follow the form submission. I recommend keeping the alienform.cgi together with the associated files for organizational purposes. At my site I can place my CGI scripts inside my web directory, and so I've created a directory named scripts and within that directory is a subdirectory for alienform named alien. So my path statement reads: /usr/users/edmiston/public_html/scripts/alien/. The UNIX command pwd can be used to identify your directory path.

   d. The host name and IP addresses of your server

   This is a safety measure to keep people at other domains from using your script. This entry includes both the domain name and the IP address of your server. For example, I use: woodfin.cs.unca.edu 152.18.18.7

   Once you edit the CGI script you needn't edit it again for additional applications.

3. Once the files are in place (i.e., the CGI scripts and associated files in one directory) and the form in the web directory, be sure to set the file permissions. The CGI script needs to be executable and the other files must be readable. chmod alienform.cgi 755
   chmod [all other files] 644

Some CGI and Perl Resources

The CGI Collection

Contains links to a number of CGI/Perl tutorials and "tips and tricks". THis resource has been very helpful to me in the past.

Server Side Includes (SSI)

The CGI Resource is an all around useful site and their page on SSI is especially helpful. Some CGI scripts require SSI.

Perl Tutorial

This NCSA tutorial is very detailed and well organized.

The CGI FAQ

Matt's Script Archives contains a FAQ (Frequently Asked Questions) that's excellent for troubleshooting.

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