<STDOUT> output to web server in CGI script

How to send print output from command shell to web server ? What is the mechanism to achieve this ? Do we need to mention this in program ?

CGI script prints output to the and this output is sent to web server. I did not see any command in the script to send output from command console to web server. So how is this achieved ? Is it like that whenever .cgi extension is used, it will autmatically send output to the webserver from ?

I was reading a book to understad this , but still cant get it.

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ISCBorisB

CGI script prints output to the <STDOUT> and this output is sent to web server

You've got it completely backwards. You (Your admins) configure some Web requests as "CGI" requests. Slightly oversimplifying,
you tell Web Server how to identify CGI Request and how to map request locator to the CGI executable module.

Upon receiving CGI Request Web Server spawns a thread, [post=126385]sets CGI Call parameters[/post] according to CGI Protocol Rules
and executes CGI module catching whatever this module prints. Upon completion Web server formats the result into
HTTP Response and sends it back to the Agent that initiated original HTTP Request.

CGI Module in turn gets call's parameters and generates/prints HTTP Headers and Content into STDOUT. Once again,
an output must be formatted according to the CGI Protocol. It should be now clear ( I hope ) that CGI Module is the program
that knows how to parse CGI Parameters and how to format CGI Output, that's it. CGI Extension is just an old convention,
you can use it or ignore it.

What is the problem you are trying to solve?

khyati

Thanks.
thats where my confusion was. I was going thru following script
[html] #!c:/usr/bin/perl -wT

print<Content-type: text/html

About this server

about this server


server name:   $ENV(SERVER_NAME)
Listenin on port:  $ENV(SERVER_PORT)
Server software: $ENV(SERVER_SOFTWARE)
CGI Version:  $ENV(GATEWAY_INTERFACE)

end_of_html[/html]

In this CGI where is the CGI module used and how ? IF there is no CGI module used, how wil the CGI protocol be followed ?

The ENV variabes are specified in the CGI modue or are these defined and specified in the web server ?

ISCBorisB

CGI itself is a protocol, not some mysterious "Module" whatever you mean by that word. Various languages have of course modules,
classes, libraries and whatnot to organise and simplify CGI usage. perl's Class for all that is simply called "CGI", see here. So...

Q. In this CGI where is the CGI module used and how?
A. No Perl CGI Modules are used in this sample.

Q. If there is no CGI module used, how will the CGI protocol be followed?
A. By printing CGI-formatted output to STDOUT. In the simplest case all you need is Content-type Header setting Mime-type
plus the following Content. Your code dutifully provides that.

Q. The ENV variables are specified in the CGI module or are these defined and specified in the web server?
A. The Environment is always set within the shell that executes your script. If you run it from the browser then the Web/App
Server that process your request will set up thread's Environment according to CGI rules and execute your CGI Script there.

For other questions - right here