in reply to Re: Multiplexing problem
in thread Multiplexing problem

Here is my code: 
---server---

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

 

$socket=new IO::Socket::INET->new(LocalPort=>2010,Proto=>'udp');
$select=IO::Select->new($socket,\*STDIN);

LOOP:
while(1)
{
 @readers=$select->can_read();
 foreach $ready (@readers)
 { 
  if($ready eq \*STDIN)
  {
   print "\n","Enter message to send to client : ";
  
   $msg_out=<STDIN>;
  
   $socket->send($msg_out);
  
   goto LOOP;
  }
  elsif($ready eq $socket)
  {
   $socket->recv($msg_in,100);
   print "\n","Peer>",$msg_in;
   goto LOOP;
  }
 }

}

exit 1;


---client---

use IO::Socket::INET;

use IO::Select;
 
$socket=new IO::Socket::INET->new(PeerPort=>2010,Proto=>'udp',PeerAddr
+=>'localhost');
$select=IO::Select->new($socket,\*STDIN);


LOOP:
while(1)
{
 @readers=$select->can_read();
 foreach $ready (@readers)
 { 
  if($ready eq \*STDIN)
  {
   print "Enter message to send to server : ";

   $msg_out=<STDIN>;
   
   
   $socket->send($msg_out);
  
  
   goto LOOP;
  }
  elsif($ready eq $socket)
  {
   $socket->recv($msg_in,100);
   print "\n","Peer>",$msg_in;
   goto LOOP;
  }
 }

}
exit 1;

[download]

Replies are listed 'Best First'.
Re^3: Multiplexing problem
by ikegami (Patriarch) on Feb 08, 2010 at 20:09 UTC

    STDIN is not a socket. You can only use select on sockets in Windows, as previously stated.

    Even if you weren't on Windows, it would be defy the purpose of select to read until you got a newline, and it doesn't make sense to use buffered I/O and select on the same handle.

[reply]
[d/l]
[select]
      Another code: 
      
use IO::Socket::INET;

use IO::Select;

syswrite(STDOUT,"----- Server Program -----\n");
 

$socket=new IO::Socket::INET->new(LocalPort=>1234,Proto=>'udp') or die
+ "socket() error: $!";

$select=IO::Select->new($socket);

LOOP:

while(1)

{

 if(@readers=$select->can_read(0.1))

 {
  $socket->recv($msg_in,128);

  syswrite(STDOUT,"\nPeer>$msg_in");


  }
 else
 {
  syswrite(STDOUT,"Enter message to send to server : ");

  sysread(STDIN,$msg_out,100);   
   
  send($socket,$msg_out,0,'localhost');
  
  goto LOOP;
 }

}

exit 1;

      [download]
      ============================== 
      
use IO::Socket::INET;

use IO::Select;


syswrite(STDOUT,"----- Client Program -----\n");
 

$socket=new IO::Socket::INET->new(PeerPort=>1234,Proto=>'udp',PeerAddr
+=>'localhost') or die "socket() error: $!";

$select=IO::Select->new($socket);



LOOP:

while(1)

{

 if(@readers=$select->can_read(0.1))

 {
  $socket->recv($msg_in,128);

  syswrite(STDOUT,"\nPeer>$msg_in");


  }
 else
 {
  syswrite(STDOUT,"Enter message to send to server : ");

  sysread(STDIN,$msg_out,100);   
   
  $socket->send($msg_out);
  
  goto LOOP;
 }

}

exit 1;

      [download]
      But when i send messages from client the server doesn't print the data on screen but in order to print it i have to change line(newline).It acts like it buffers the data.I would appreciate any ideas.
[reply]
[d/l]
[select]
        new IO::Socket::INET->new(...)

        [download]
        should simply be 
        IO::Socket::INET->new(...)

        [download]

        If you have a buffering issue, just autoflush. For STDOUT, the following will do: 

        $|=1;

        [download]

        Your real problem is that sysread(STDIN,$msg_out,100); blocks.

        I started writing a solution. But honestly, it would be much simpler to avoid select() and use threads.

[reply]
[d/l]
[select]
        I'll get back to you. Very busy right now
[reply]

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