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Re^2: IO Socket buffer flushing

by eric256 (Parson)
on Jan 29, 2010 at 16:55 UTC ( [id://820365] : note . print w/replies, xml ) Need Help??

in reply to Re: IO Socket buffer flushing
in thread IO Socket buffer flushing

Just playing around with sockets (cause its fun) I worked up the following code. Its not better realy, just different, and doesn't count on send a specific amount of info each time, intead it uses ->say and ->getline to send whole lines of data. I had to use chomp a couple times and i'm wondering if that could be avoided, but here you have it.

#!/usr/bin/perl #server use strict; use warnings; use IO::Socket; $| = 1; my $nonblocking = 1; my $sock = new IO::Socket::INET( LocalHost => "localhost", LocalPort => 7890, Proto => "tcp", Listen => SOMAXCONN, Reuse => 1, Timeout => 20, ); if ($sock) { print "A socket created on LocalHost listening on LocalPort\n"; } else { die "Error - no listening socket created : $!"; } my $flush = 1; while (my ($new_sock,$c_addr) = $sock->accept()) { my ($client_port, $c_ip) = sockaddr_in($c_addr); my $client_ipnum = inet_ntoa($c_ip); my $client_host =gethostbyaddr($c_ip, AF_INET); print "Got a connection from: $client_host"," [$client_ipnum] \n"; print "Created new socket for reading or writing data to Client\n" +; $new_sock->blocking(1); my $buf; $buf = $new_sock->getline(); chomp($buf); print "Recieved 1 '$buf'\n"; $new_sock->say($buf); $buf = $new_sock->getline(); chomp($buf); print "Recieved 2 '$buf'\n"; $new_sock->say("12"); }
#!/usr/bin/perl #client use strict; use warnings; use IO::Socket; #To flush the buffer print statements $| = 1; my $sock = new IO::Socket::INET( PeerAddr => 'localhost', PeerPort => +7890, Proto => 'tcp'); if ($sock) { print "A tcp socket on localhost connected to 7890\n"; } else { die "Error: $!"; } my $buf = "1234567890"; $sock->say($buf); print "Sent '$buf'\n"; $buf = $sock->getline(); chomp($buf); print "Bytes 10 = '$buf'\n"; $sock->say("1"); $buf = $sock->getline(); chomp($buf); print "Bytes 2 = '$buf'\n";

Eric Hodges

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Re^3: IO Socket buffer flushing
by ikegami (Patriarch) on Jan 29, 2010 at 17:23 UTC

    TCP provides a stream of bytes. You need to do your own record delimiting. readline works because it waits until a delimiter is found.

    If you need a sysread version (perhaps so you can use select), see Re^3: Can a socket listen for multiple hosts? for an example.