Provided by: libplrpc-perl_0.2020-2_all bug


       RPC::PlClient - Perl extension for writing PlRPC clients


         require RPC::PlClient;

         # Create a client object and connect it to the server
         my $client = RPC::PlClient->new('peeraddr' => '',
                                         'peerport' => 2570,
                                         'application' => 'My App',
                                         'version' => '1.0',
                                         'user' => 'joe',
                                         'password' => 'hello!');

         # Create an instance of $class on the server by calling $class->new()
         # and an associated instance on the client.
         my $object = $client->Call('NewHandle', $class, 'new', @args);

         # Call a method on $object, effectively calling the same method
         # on the associated server instance.
         my $result = $object->do_method(@args);


       PlRPC (Perl RPC) is a package that simplifies the writing of Perl based client/server
       applications. RPC::PlServer is the package used on the server side, and you guess what
       RPC::PlClient is for. See RPC::PlServer(3) for this part.

       PlRPC works by defining a set of methods that may be executed by the client.  For example,
       the server might offer a method "multiply" to the client. Now a function call

           @result = $client->Call('multiply', $a, $b);

       on the client will be mapped to a corresponding call

           $server->multiply($a, $b);

       on the server. The function calls result will be transferred to the client and returned as
       result of the clients method. Simple, eh? :-)

   Client methods
       $client = new(%attr);
           (Class method) The client constructor. Returns a client object, connected to the
           server. A Perl exception is thrown in case of errors, thus you typically use it like

               $client = eval { RPC::PlClient->new ( ... ) };
               if ($@) {
                   print STDERR "Cannot create client object: $@\n";
                   exit 0;

           The method accepts a list of key/value pairs as arguments. Known arguments are:

           timeout These correspond to the attributes PeerAddr, PeerPort, Proto, Type and Timeout
                   of IO::Socket::INET. The server connection will be established by passing them
                   to IO::Socket::INET->new().

           socket  After a connection was established, the IO::Socket instance will be stored in
                   this attribute. If you prefer establishing the connection on your own, you may
                   as well create an own instance of IO::Socket and pass it as attribute socket
                   to the new method. The above attributes will be ignored in that case.

                   it is part of the PlRPC authorization process, that the client must obeye a
                   login procedure where he will pass an application name, a protocol version and
                   optionally a user name and password.  These arguments are handled by the
                   servers Application, Version and User methods.

                   Set this to off (default, no compression) or gzip (requires the Compress::Zlib

           cipher  This attribute can be used to add encryption quite easily. PlRPC is not bound
                   to a certain encryption method, but to a block encryption API. The attribute
                   is an object supporting the methods blocksize, encrypt and decrypt. For
                   example, the modules Crypt::DES and Crypt::IDEA support such an interface.

                   Note that you can set or remove encryption on the fly (putting "undef" as
                   attribute value will stop encryption), but you have to be sure, that both
                   sides change the encryption mode.


                       use Crypt::DES;
                       $cipher = Crypt::DES->new(pack("H*", "0123456789abcdef"));
                       $client = RPC::PlClient->new('cipher' => $cipher,

                   The size of messages exchanged between client and server is restricted, in
                   order to omit denial of service attacks. By default the limit is 65536 bytes.

           debug   Enhances logging level by emitting debugging messages.

           logfile By default the client is logging to syslog (Unix) or the event log (Windows).
                   If neither is available or you pass a TRUE value as logfile, then logging will
                   happen to the given file handle, an instance of IO::Handle. If the value is
                   scalar, then logging will occur to stderr.


                     # Logging to stderr:
                     my $client = RPC::PlClient->new('logfile' => 1, ...);

                     # Logging to 'my.log':
                     my $file = IO::File->new('my.log', 'a')
                         || die "Cannot create log file 'my.log': $!";
                     my $client = RPC::PlClient->new('logfile' => $file, ...);

       @result = $client->Call($method, @args);
           (Instance method) Calls a method on the server; the arguments are a method name of the
           server class and the method call arguments. It returns the method results, if
           successfull, otherwise a Perl exception is thrown.


             @results = eval { $client->Call($method, @args };
             if ($@) {
                 print STDERR "An error occurred while executing $method: $@\n";
                 exit 0;

       $cobj = $client->ClientObject($class, $method, @args)
           (Instance method) A set of predefined methods is available that make dealing with
           client side objects incredibly easy: In short the client creates a representation of
           the server object for you. Say we have an object $sobj on the server and an associated
           object $cobj on the client: Then a call

             @results = $cobj->my_method(@args);

           will be immediately mapped to a call

             @results = $sobj->my_method(@args);

           on the server and the results returned to you without any additional programming.
           Here's how you create $cobj, an instance of RPC::PlClient::Object:

             my $cobj = $client->ClientObject($class, 'new', @args);

           This will trigger a call

             my $sobj = $class->new(@args);

           on the server for you. Note that the server has the ability to restrict access to both
           certain classes and methods by setting $server->{'methods'} appropriately.


       We'll create a simple example application, an MD5 client. The server will have installed
       the MD5 module and create digests for us. We present the client part only, the server
       example is part of the RPC::PlServer man page. See RPC::PlServer(3).


           use strict;               # Always a good choice.

           require RPC::PlClient;

           # Constants
           my $MY_APPLICATION = "MD5_Server";
           my $MY_VERSION = 1.0;
           my $MY_USER = "";           # The server doesn't require user
           my $MY_PASSWORD = "";       # authentication.

           my $hexdigest = eval {
               my $client = RPC::PlClient->new
                   ('peeraddr'    => '',
                    'peerport'    => 2000,
                    'application' => $MY_APPLICATION,
                    'version'     => $MY_VERSION,
                    'user'        => $MY_USER,
                    'password'    => $MY_PASSWORD);

               # Create an MD5 object on the server and an associated
               # client object. Executes a
               #     $context = MD5->new()
               # on the server.
               my $context = $client->ClientObject('MD5', 'new');

               # Let the server calculate a digest for us. Executes a
               #     $context->add("This is a silly string!");
               #     $context->hexdigest();
               # on the server.
               $context->add("This is a silly string!");
           if ($@) {
               die "An error occurred: $@";

           print "Got digest $hexdigest\n";


       The PlRPC-modules are

         Copyright (C) 1998, Jochen Wiedmann
                             Email: jochen.wiedmann at

         All rights reserved.

       You may distribute this package under the terms of either the GNU General Public License
       or the Artistic License, as specified in the Perl README file.


       PlRPC::Server(3), Net::Daemon(3), Storable(3), Sys::Syslog(3), Win32::EventLog

       An example application is the DBI Proxy client: