iTP Secure WebServer System Administrator's Guide (iTPWebSvr 5.1+)

Using Common Gateway Interface (CGI) Programs

iTP Secure WebServer System Administrator’s Guide—522659-001

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Returning Output

For example, if a user name (John J. Smith) and an e-mail address

(jsmith@xyz.com) are entered into an HTML form as input, these data items would

be formatted into input parameters as follows:

NAME=John+J.+Smith&EMAIL=jsmith@xyz.com

The input parameters must be entered exactly as required.

The environment variable CONTENT_LENGTH specifies the number of bytes on

standard input.

For detailed information about processing forms input parameters, consult an

appropriate HTML resource.

Returning Output

Any output a CGI program writes to standard output is passed by the server to the web

client. This output has three components:

•

One or more HTTP response headers

These headers contain descriptive information about the server response to a

request, such as the content (data) type, the number of bytes, and the expiration

time.

•

A blank line

This blank line is mandatory, even no content follows it. This requirement is

imposed by RFC 822; to see RFC 822, use the following URL:

http://www.cis.ohio-state.edu/htbin/rfc/rfc822.html

•

The response content

The response content is the actual object being returned to a web client. For

example, this content might consist of an HTML document, an image, or an audio

file.

The following is a very simple example of output from a CGI program:

Content-type: text/html

<TITLE>Example output</TITLE>

</HEAD><BODY>

This is the HTML document generated by a CGI program.

</BODY></HTML>