Perl in a Nutshell, 2nd Edition

HTTP::Response

Responses from a web server are described by HTTP::Response objects. An HTTP response message contains a status line, headers, and any content data that was requested by the client (such as an HTML file). The status line is the minimum requirement for a response. It contains the version of HTTP that the server is running, a status code indicating the success, failure, or other condition the request received from the server, and a short message describing the status code.

If LWP has problems fulfilling your request, it internally generates an HTTP::Response object and fills in an appropriate response code. In the context of web client programming, you’ll usually get an HTTP::Response object from LWP::UserAgent and LWP::RobotUA.

If you plan to write extensions to LWP or to a web server or proxy server, you might use HTTP::Response to generate your own responses.

The constructor for HTTP::Response looks like this:

$resp = HTTP::Response->new (rc, [msg, [header, [content]]]);

In its simplest form, an HTTP::Response object can contain just a response code. If you would like to specify a more detailed message than “OK” or “Not found,” you can specify a text description of the response code as the second parameter. As a third parameter, you can pass a reference to an HTTP::Headers object to specify the response headers. Finally, you can also include an entity body in the fourth parameter as a scalar.

For client applications, it is unlikely that you will build your own response ...