Re^5: Tk Realtime data aquisition

So, I tried a few things the first was to see if the data was coming across the socket. Here's my simple script:

#!/usr/bin/perl

use IO::Socket; 
my $sock = new IO::Socket::INET ( 
    LocalHost => 'localhost', 
    LocalPort => '7070', 
    Proto => 'tcp', 
    Listen => 1, 
    Reuse => 1, 
); die "Could not create socket: $!\n" unless $sock;


my $new_sock = $sock->accept(); 
while(<$new_sock>) { 
    print $_;  
 } 
close($sock);
__END__
[download]

And it works, data comes across the socket, and shows up in the command window. I do think the problem is in the fileevent. But, I can do the read like I did in my small script, but how do I pass what is read to TK and then use it within its subroutines to build the graph?

Comment on Re^5: Tk Realtime data aquisition Download Code

Replies are listed 'Best First'.
Re^6: Tk Realtime data aquisition by zentara (Cardinal) on May 09, 2009 at 11:00 UTC
Hi, a couple of quick ways....clunky hacks for win32. `while(<$new_sock>) { my $input = chomp $_; #print $_; $canvas->update_graph( $input ) # pseudocode to demo point :-) $mw->update; # force the event loop to auto update the window }` [download] Ideally, you don't want to use a $mw->update in a while() loop. A timer is better, but may not be as fast.....although it will allow you to run other subs in the eventloop simultaneously with the socket connection.... like watching for a value to trip an alarm. `my $timer = $mw->repeat(10, \&update_graph);` [download] thats better. Then in the update_graph sub, read your socket, and update the canvas. You can start a second timer to watch for values, as they come in( store the last 10 values in a buffer)). It's all an event-loop system underneath......very powerful and useful once you get the idea. :-) Gtk2's event-loop is even more powerful than Tk's. I'm not really a human, but I play one on earth. Old Perl Programmer Haiku	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re^6: Tk Realtime data aquisition
by zentara (Cardinal) on May 09, 2009 at 11:00 UTC

while(<$new_sock>) {
    my $input = chomp $_; 
    #print $_;  
    $canvas->update_graph( $input  )  # pseudocode to demo point :-)
    $mw->update;   # force the event loop to auto update the window
  }
[download]

Ideally, you don't want to use a $mw->update in a while() loop. A timer is better, but may not be as fast.....although it will allow you to run other subs in the eventloop simultaneously with the socket connection.... like watching for a value to trip an alarm.

my $timer = $mw->repeat(10, \&update_graph);
[download]

I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku

[reply]
[d/l]
[select]