########################server.pl
#!/usr/bin/perl

$args=@ARGV;
if($args!=2)
{
	print "usage:server.pl [localport] [localfile]\n";
	exit;
}
$port=$ARGV[0];
$file=$ARGV[1];

use IO::Socket;
$skt=IO::Socket::INET->new(LocalAddr=>'0.0.0.0',LocalPort=>$port,Proto=>'tcp',Listen=>5)||do{
	print $!."\n";
	exit;
};
$skt->autoflush(1);
print "Ready on port $port ...\n";
$newskt=$skt->accept;
$newskt->sockopt(SO_SNDLOWAT,2048);
$newskt->autoflush(1);
print "client is coming ...\n";
open (FILE,">$file")||die $!;
while($n=sysread($newskt,$buf,2))
{
	$total+=$n;
	print FILE $buf;
	print "received:".$total."\r";
}
close FILE;
$newskt->close();
$skt->close();
print "\nDone.($file)\n";

########################client.pl
#!/usr/bin/perl

$args=@ARGV;
if($args!=3)
{
	print "usage:client.pl [peerhost] [peerport] [localfile]\n";
	exit;
}

$host=$ARGV[0];
$port=$ARGV[1];
$file=$ARGV[2];

use IO::Socket;
$skt=IO::Socket::INET->new(PeerAddr=>$host,PeerPort=>$port,Proto=>'tcp')||do{
	print $!."\n";
	exit;
};
print "Begin ...\n";
open (FILE,"$file")||die $!;
binmode FILE;

while($n=read(FILE,$buf,512))
{
	$total+=$n;
	print $skt $buf;
	print "sent:".$total."\r";
}
close FILE;
$skt->close();
print "\nDone.(local $file to remote $host)\n";