perldoc > LWP::Simple

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📛 NAME

LWP::Simple - simple procedural interface to LWP

🚀 Quick Reference

Use Case	Command	Description
Fetch a URL into a variable	my $content = get($url);	Returns document content, or undef on failure
Fetch and print URL	getprint($url);	Prints to STDOUT; returns HTTP response code
Save URL to file	getstore($url, $file);	Stores document in file; returns HTTP code
Mirror URL (conditional fetch)	mirror($url, $file);	Uses If-Modified-Since and Content-Length; returns HTTP code
Get document headers only	my ($type, $len, $mod, $exp, $srv) = head($url);	Returns content type, document length, modified time, expires, server
Check if request succeeded	if (is_success($code)) { ... }	True for 2xx response codes
One-liner from command line	perl -MLWP::Simple -e 'getprint "http://..."'	Quick download without a script

📋 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 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).

🔧 FUNCTIONS

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

📥 get

my $res = get($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

my $res = head($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

my $code = getprint($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

my $code = getstore($url, $file);

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

🪞 mirror

my $code = mirror($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.

📊 STATUS CONSTANTS

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

🔍 CLASSIFICATION FUNCTIONS

The HTTP::Status classification functions are:

✅ is_success

my $bool = is_success($rc);

True if response code indicated a successful request.

❌ is_error

my $bool = is_error($rc);

True if response code indicated that an error occurred.

⚠️ CAVEAT

Note that if you are using both LWP::Simple and the very popular CGI 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

📛 NAME 🚀 Quick Reference 📋 SYNOPSIS 📖 DESCRIPTION 🔧 FUNCTIONS 📊 STATUS CONSTANTS 🔍 CLASSIFICATION FUNCTIONS ⚠️ CAVEAT 📚 SEE ALSO