LWP::Simple

NAME
SYNOPSIS
DESCRIPTION
CAVEAT
SEE ALSO

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NAME

LWP::Simple − simple procedural interface to LWP

SYNOPSIS

 perl −MLWP::Simple −e 'getprint "http://www.sn.no"'
 use LWP::Simple;
 $content = get("http://www.sn.no/");
 die "Couldn't get it!" unless defined $content;
 if (mirror("http://www.sn.no/", "foo") == RC_NOT_MODIFIED) {
     ...
 }
 if (is_success(getprint("http://www.sn.no/"))) {
     ...
 }

DESCRIPTION

This module is meant for people who want a simplified view of the libwww-perl library. It should also be suitable for one-liners. If you need more control or access to the header fields in the requests sent and responses received, then you should use the full object-oriented interface provided by the "LWP::UserAgent" module.

The following functions are provided (and exported) by this module:
get($url)

The get() function will fetch the document identified by the given URL and return it. It returns "undef" if it fails. The $url argument can be either a string or a reference to a URI object.

You will not be able to examine the response code or response headers (like ’Content−Type’) when you are accessing the web using this function. If you need that information you should use the full OO interface (see LWP::UserAgent).

head($url)

Get document headers. Returns the following 5 values if successful: ($content_type, $document_length, $modified_time, $expires, $server)

Returns an empty list if it fails. In scalar context returns TRUE if successful.

getprint($url)

Get and print a document identified by a URL . The document is printed to the selected default filehandle for output (normally STDOUT ) as data is received from the network. If the request fails, then the status code and message are printed on STDERR . The return value is the HTTP response code.

getstore($url, $file)

Gets a document identified by a URL and stores it in the file. The return value is the HTTP response code.

mirror($url, $file)

Get and store a document identified by a URL , using If-modified-since, and checking the Content-Length. Returns the HTTP response code.

This module also exports the HTTP::Status constants and procedures. You can use them when you check the response code from getprint(), getstore() or mirror(). The constants are:

   RC_CONTINUE
   RC_SWITCHING_PROTOCOLS
   RC_OK
   RC_CREATED
   RC_ACCEPTED
   RC_NON_AUTHORITATIVE_INFORMATION
   RC_NO_CONTENT
   RC_RESET_CONTENT
   RC_PARTIAL_CONTENT
   RC_MULTIPLE_CHOICES
   RC_MOVED_PERMANENTLY
   RC_MOVED_TEMPORARILY
   RC_SEE_OTHER
   RC_NOT_MODIFIED
   RC_USE_PROXY
   RC_BAD_REQUEST
   RC_UNAUTHORIZED
   RC_PAYMENT_REQUIRED
   RC_FORBIDDEN
   RC_NOT_FOUND
   RC_METHOD_NOT_ALLOWED
   RC_NOT_ACCEPTABLE
   RC_PROXY_AUTHENTICATION_REQUIRED
   RC_REQUEST_TIMEOUT
   RC_CONFLICT
   RC_GONE
   RC_LENGTH_REQUIRED
   RC_PRECONDITION_FAILED
   RC_REQUEST_ENTITY_TOO_LARGE
   RC_REQUEST_URI_TOO_LARGE
   RC_UNSUPPORTED_MEDIA_TYPE
   RC_INTERNAL_SERVER_ERROR
   RC_NOT_IMPLEMENTED
   RC_BAD_GATEWAY
   RC_SERVICE_UNAVAILABLE
   RC_GATEWAY_TIMEOUT
   RC_HTTP_VERSION_NOT_SUPPORTED

The HTTP::Status classification functions are:
is_success($rc)

True if response code indicated a successful request.

is_error($rc)

True if response code indicated that an error occurred.

The module will also export the LWP::UserAgent object as $ua if you ask for it explicitly.

The user agent created by this module will identify itself as "LWP::Simple/#.##" and will initialize its proxy defaults from the environment (by calling $ua−>env_proxy).

CAVEAT

Note that if you are using both LWP::Simple and the very popular CGI .pm module, you may be importing a "head" function from each module, producing a warning like "Prototype mismatch: sub main::head ($) vs none". Get around this problem by just not importing LWP::Simple’s "head" function, like so:

        use LWP::Simple qw(!head);
        use CGI qw(:standard);  # then only CGI.pm defines a head()

Then if you do need LWP::Simple’s "head" function, you can just call it as "LWP::Simple::head($url)".

SEE ALSO

LWP , lwpcook, LWP::UserAgent, HTTP::Status, lwp-request, lwp-mirror

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