In my CGI script, I have a function that prints an HTML page to stdout. The function is imported from a custom module. I want to show the HTTP response headers in the HTML page.

I can easily show the request headers from printing the server environment variables in the HTML, but it is the response headers that ellude me.

I looked at HTTP::Response. But to use HTTP::Response, I would have to initiate a new request. If I make a fresh request in the module and capture the response, then that response would be different from the one involving the HTML page.

Note: any code would be in my module and not in the CGI script. Don't try to solve this in the CGI script (the caller's namespace). For example: 

Package My::Module;
require Exporter;
@My::Module::ISA    = qw(Exporter);
@My::Module::EXPORT = qw(the-function);

sub the-function {

print "Content-type: text/html\n\n";

print <<HTML;
Here are the HTTP REQUEST headers:
<p>
HTTP Request: $ENV{'REQUEST_METHOD'} $0 $ENV{'SERVER_PROTOCOL'}
<br>
Host: $ENV{'HTTP_HOST'}
<br>
User-Agent: $ENV{'HTTP_USER_AGENT'}
<br>
Accept: $ENV{'HTTP_ACCEPT_ENCODING'}
<br>
Accept-Language: $ENV{'HTTP_ACCEPT_LANGUAGE'}
<br>
Accept-Charset: $ENV{'HTTP_ACCEPT_CHARSET'}
<br>
Keep-Alive: $ENV{'HTTP_KEEP_ALIVE'}
<br>
Connection: $ENV{'HTTP_CONNECTION'}
<p>

SORRY -- I don't know how to show you the HTTP --RESPONSE-- Headers . 
+. .

HTML
}
1;

Package Main;

#!/usr/bin/perl

use My::Module;

the-function();

__END__

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I hope the code makes my question clearer.

In reply to Showing HTTP response headers by jacques

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