earlati2 has asked for the wisdom of the Perl Monks concerning the following question:

I suppose my question is a very simple one, but I didn't find a real solution so I hope someone ca help.

I have 2 programma which send each other data using the socket via module Io::Socket

the server is somethink like this:

use IO::Socket;

my ( $stmp, $nchar );
$| = 1;
my $sock = new IO::Socket::INET (
                                 LocalHost => 'localhost',
                                 LocalPort => '2040',
                                 Proto => 'tcp',
                                 Listen => 1,
                                 Reuse => 1,
                                );
die "Could not create socket: $!\n" unless $sock;

$sock->autoflush();

while( 1 )
{
   my $new_sock = $sock->accept();

   $| = 1;
   $new_sock->autoflush();
   while(1)
   {
      $nchar = read( $new_sock, $stmp, 1 );  
      print "$stmp";
      print $new_sock "$stmp";
   }
}

close($sock);

[download]

-------  while the cliente is as follow

my $sock = new IO::Socket::INET (
   PeerAddr => 'localhost',
   PeerPort => $remote_port,  Proto => 'tcp',
);

die "Could not create socket: $!\n" unless $sock;
   $sock->autoflush();

ae_util::mylog( "SendSOCKT: $msg " );

print $sock "$msg\n";

 $stmp = <$sock>;
 chomp $stmp;
 ae_util::mylog( "AnswSOCKT: $stmp " );
 close( $sock );

[download]

The problem is that if I send a message terminated with new-line ( as print $sock "$msg\n"; ) is all ok

If I send the message without the newline at the end the program hangs, the server receive the data , and mybe send the answer , but the cliente didn't receive the answer.

Where I' m wrong in this and how can send message without end-line terninator on the socket ?

thank for the help, Enzo

Formatting cleansed by holli as per consideration

Replies are listed 'Best First'.
Re: how send message without new-line terminator on IO::Socket
by Corion (Patriarch) on Jul 26, 2006 at 08:32 UTC
[reply]
      I only need to say why if I send a message terminated by a 
new-line the server read the message , without the new-line 
I got no answer.


      
If the server is something like this :
 while( 1 )
 {
    my $new_sock = $sock->accept();
    $stmp = <$new_sock>;
    print "$stmp";
    print $new_sock "$stmp\n";
    close($new_sock);
 }
 close($sock);

the server hang waiting for a newline.
what cha I do to avoid the server waiting for the newline.
[reply]

        You cannot use <$new_sock> anymore, because that waits for a newline character. You need to use read instead. You also likely want nonblocking IO using the four-argument version of select. Likely, IO::Select wraps this up nicely for you. There is example code on how to use IO::Select in its documentation. For select, I didn't find any nice documentation.

        Basically, select and IO::Select return once a socket is ready to receive more data or to send more data, and tell you which socket(s).

        There are three multiplexing frameworks I know of that handle nonblocking sockets in a manner that is more or less inconveniencing - POE, Danga::Socket and Coro. All three have different uses and different shortcomings.

[reply]
[d/l]
[select]

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