NAME
IO::Lambda::Socket - wrapper condition for socket functions
DESCRIPTION
This module provides a set of convenient wrapper conditions for sockets that function as sources of asynchronous events. The condition names are homonyms of the underlying socket functions: accept
, connect
, recv
, and send
. The module doesn't account for much lower-lever socket machinery, the programmer is expected to create non-blocking sockets using IO::Socket
or Socket
modules.
SYNOPSIS
use IO::Socket;
use IO::Lambda qw(:all);
use IO::Lambda::Socket qw(:all);
TCP
my $server = IO::Socket::INET-> new(
Listen => 5,
LocalPort => 10000,
Blocking => 0,
ReuseAddr => 1,
);
die $! unless $server;
my $serv = lambda {
context $server;
accept {
my $conn = shift;
die "error:$conn\n" unless ref($conn);
again;
context getline, $conn, \(my $buf = '');
tail {
next unless defined $_[0];
print "you said: $_[0]";
again;
}}
};
sub connector
{
my $id = shift;
lambda {
my $client = IO::Socket::INET-> new(
PeerAddr => 'localhost',
PeerPort => 10000,
Blocking => 0,
);
context $client;
connect {
die "error:$_[0]\n" if @_;
print $client "hello from $id\n";
}}
}
$serv-> wait_for_all( map { connector($_) } 1..5);
UDP
my $server = IO::Socket::INET-> new(
LocalPort => 10000,
Blocking => 0,
Proto => 'udp',
);
die $! unless $server;
my $serv = lambda {
context $server, 256;
recv {
my ($addr, $msg) = @_;
my ($port, $iaddr) = sockaddr_in($addr);
my $host = inet_ntoa($iaddr);
die "error:$msg\n" unless defined $addr;
print "udp_recv($host:$port): $msg\n";
again;
}
};
sub connector
{
my $id = shift;
lambda {
my $client = IO::Socket::INET-> new(
PeerAddr => 'localhost',
PeerPort => 10000,
Proto => 'udp',
Blocking => 0,
);
context $client, "hello from $id";
send {
die "send error:$_[1]\n" unless $_[0];
}}
}
$serv-> wait_for_all( map { connector($_) } 1..3);
API
- accept($socket, $deadline=undef) -> ($new_socket | undef,$error)
-
Expects a stream
$socket
in a non-blocking listening state. Finishes either after a new connection arrives, or after$deadline
is expired. Returns a new socket serving the new connection on success,undef
and an error string on failure. The error string is eithertimeout
or$!
.See also "accept" in perlfunc.
- connect($socket, $deadline=undef) -> (()|$error)
-
Expects stream
$socket
in a non-blocking connect state. Finishes either after the connection succeeds, or after$deadline
is expired. Returns no parameters on success, and an error string on failure. The error string is eithertimeout
or$!
(or$^E
on win32).See also "connect" in perlfunc.
- recv($socket, $length, $flags=0, $deadline=undef) -> ($addr,$msg | undef,$error)
-
Expects a non-blocking datagram
$socket
. After the socket becomes readable, tries to read$length
bytes usingCORE::recv
call. Returns remote address (packed) and the received message on success. Returnsundef
and an error string on failure. The error string is eithertimeout
or$!
.See also "recv" in perlfunc.
- send($socket, $msg, $flags, $to=undef, $deadline=undef) -> ($nbytes | undef,$error)
-
Expects a non-blocking datagram
$socket
. After the socket becomes writable, tries to write$msg
usingCORE::send
call. Depending whether$to
is defined or not, 4- or 3- parameter version ofCORE::send
is used. Returns number of bytes sent on success. On failure returnsundef
and an error string. The error string is eithertimeout
or$!
.See also "send" in perlfunc.
LICENSE AND COPYRIGHT
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
AUTHOR
Dmitry Karasik, <dmitry@karasik.eu.org>.