RPC::pClient 0.1005

RPC::pClient is a Perl extension for writing pRPC clients.

SYNOPSIS

use RPC::pClient;

$sock = IO::Socket::INET->new(PeerAddr => joes.host.de,
PeerPort => 2570,
Proto => tcp);

$connection = new RPC::pClient(sock => $sock,
application => My App,
version => 1.0,
user => joe,
password => hello!);

pRPC (Perl RPC) is a package that simplifies the writing of Perl based client/server applications. RPC::pServer is the package used on the server side, and you guess what RPC::pClient is for. See RPC::pClient(3) for this part.
pRPC works by defining a set of of functions that may be executed by the client. For example, the server might offer a function "multiply" to the client. Now a function call

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

on the client will be mapped to a corresponding call

multiply($con, $data, $a, $b);

on the server. (See the funcTable description below for $data.) The function calls result will be returned to the client and stored in the array @result. Simple, eh?

Client methods

new

The client constructor. Returns a client object or an error string, thus you typically use it like this:

$client = RPC::pClient->new ( ... );
if (!ref($client)) {
print STDERR "Error while creating client object: $clientn";
} else {
# Do real stuff
...
}

Call

calls a function on the server; the arguments are a function name, followed by function arguments. It returns the function results, if successfull. After executing Call() you should always check the error attribute: An empty string indicates success. Thus the equivalent to

$c = Add($a, $b)
# Use $c
...

is

$c = $client->Call("Add", $a, $b);
if ($client->error) {
# Do something in case of error
...
} else {
# Use $c
...
}

CallInt

Similar to and internally used by Call. Receives the same arguments, but the result is prepended by a status value: If this status value is TRUE, then all went fine and the following result array is valid. Otherwise an error occurred and the error message follows immediately after the status code. Example:

my($status, @result) = $client->CallInt("Add", $a, $b);
if (!$status) {
# Do something in case of error
my $errmsg = shift @result || "Unknown error";
...
} else {
...
}

Encrypt

This method can be used to get or set the cipher attribute, thus the encryption mode. If the method is passed an argument, the argument will be used as the new encryption mode. (undef for no encryption.) In either case the current encryption mode will be returned. Example:

# Get the current encryption mode
$mode = $server->Encrypt();

# Currently disable encryption
$server->Encrypt(undef);

# Switch back to the old mode
$server->Encrypt($mode);