Re: trying to write simple sockets client on Windows

I presume this is the sort of thing you want (this is a server that accepts conns and listens/writes to them all asyncronously) but a client would be similar. It is not entirely clear what you actually want to do:

use IO::Select;
use IO::Socket;

$lsn = new IO::Socket::INET(Listen => 1, LocalPort => 8080);
$sel = new IO::Select( $lsn );

while(@ready = $sel->can_read) {
    foreach $fh (@ready) {
        if($fh == $lsn) {
            # Create a new socket to handle more conns
            $new = $lsn->accept;
            $sel->add($new);     # register it with IO::Select
        }
        else {
            # Process socket
            my $data = <$fh>;
            if ( $data =~ m/exit/i ) {
                print $fh "Sayonara!\n";
                $sel->remove($fh);
                $fh->close;
            }
            else {
                print $fh "Hello $data\n";
            }
        }
    }
}
[download]

Run the server in a command window. Open any number of other command windows and telnet localhost 8080 Talk to the server and it will talk back to that telnet session until you type exit.

cheers

tachyon

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Re: Re: trying to write simple sockets client on Windows by Anonymous Monk on Apr 14, 2004 at 06:03 UTC
Thanks tachyon. All i want to do is connect to my server and send off a file of test commands one by one ,capturing the incoming replies so that they can be logged and processed and more commands added to the send queue depending on the incoming. I guess the closest analogy would be an IRC client where i can receive messages in reply to my client or just receive a message from another client connected to the same server. All the client examples i can find only deal with a very simple client thats either synchromous or only handles sends I had this before and it works great. die "can't fork: $!" unless defined($kidpid = fork()); if ($kidpid) { # We are the parent. Handle incoming my $header; my $body; while(1) { while (defined sysread $handle,$header,9,0) { print $header,"\n"; if($header =~ m/([A-Z]{4})(\d{5})/) { my $messagetype = $1; if($2 != 00000) { $2 =~ m/0+(\d+)/; #remove sysread $handle,$body,$1,0; #receive am +ount specified in header } check_header_type $messagetype, $body, $handle; #do t +hings with this message } } } kill("TERM" => $kidpid); # send SIGTERM to child } ############################################### # Child Process ############################################### else { # Child. handle all sends while ($line = <INPUTFILE>) { chomp $line; if(!($line =~ m/\A#/)) #check for '#' in file as comment s +ign {syswrite DEBUG, "Got Line\n"; my $bod = add_header($line); syswrite $handle, $bod; } } } [download] but im stuck in cygwin, no debugging support, and passing new messages to the child process to send is starting to complicate things (from what i know)just for hacked up client. So really im trying to get the above working smoothly without fork. thanks	[reply] [d/l]
Re^2: trying to write simple sockets client on Windows by Anonymous Monk on Apr 14, 2004 at 05:34 UTC
Just to clarify a single important point: yes this code can handle multiple simultaneous client connections, but there is one limitation: the server can only deal with one client at any one moment in time. So if the server takes a lot of processing time to handle client input, then all other clients will have to wait in line for their turn to communicate with the server. This is not a big deal with most servers that communicate back and forth one a one-line-at-a-time basis, but as soon as you throw in extreme processing or any sleep()s, etc, things can back up quickly.	[reply]