tcp socket 简单通话

#!/usr/bin/perl -w
#
use strict;
use IO::Handle;
use Socket;

my ($bytes_out, $bytes_in) = (0,0);

my $host = shift || 'localhost';
my $port = shift || getservbyname('echo', 'tcp');

my $protocol = getprotobyname('tcp');

socket(SOCK, AF_INET, SOCK_STREAM, $protocol) or die 'sock() failed: $!';
my $packed_add = inet_aton($host);
my $dest_add = sockaddr_in($port, $packed_add);

connect(SOCK, $dest_add) or die "connet() failed: $!";

SOCK->autoflush(1);

while( 1 ){
        print "Client:";
        my $msg_out = <>;
#print SOCK "Client:".$msg_out;
        send(SOCK, "Client:".$msg_out, 0);
        my $msg_in = <SOCK>;
        print $msg_in;

        $bytes_out += length($msg_out);
#$bytes_in += length($msg_in);

}

close SOCK;
#print STDERR "bytes_sent = $bytes_out, bytes_received = $bytes_in\n";

server:

#!/usr/bin/perl -w
#
use strict;
use Socket;
use IO::Handle;

my ($bytes_in, $bytes_out) = (0, 0);
my $port = shift || '3000';
my $protocol = getprotobyname('tcp');

socket(SOCK, AF_INET, SOCK_STREAM, $protocol) or die "socket() failed:$!";
setsockopt(SOCK, SOL_SOCKET, SO_REUSEADDR, 1) or die " canot set so_reuseadd:$!";

my $my_addr = sockaddr_in($port, INADDR_ANY);
bind(SOCK, $my_addr) or die"bind() failed: $!";
listen(SOCK, SOMAXCONN) or die "listen() failed: $!";

warn "waiting for incoming connections on port $port ...\n";

while(1){
        next unless my $remote_addr = accept(SESSION, SOCK);
        my ($port, $hisaddr) = sockaddr_in($remote_addr);
        warn "Connection from [", inet_ntoa($hisaddr), ", $port]\n";

        SESSION->autoflush(1);
        while(<SESSION>){
                $bytes_in += length($_);
                chomp;
                print $_."\n";

#my $msg_out = (scalar reverse $_) . "\n";
                print "Server:";
                my $msg_out = <>;
                print SESSION "Server:".$msg_out;
                $bytes_out += length($msg_out);
        }
        warn " Connection from [", inet_ntoa($hisaddr), ", $port] finished\n";
        close SESSION;

}

close SOCK;