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