Ruby Bug? Windows and UDPSocket and Errno:ENOTCONN

[John Carter]

If I have a pair of Win2k Ruby processes bouncing UDP packets back and
forth...

After awhile one of them dies with Errno::ENOTCONN

The code works under Linux but not under Win2k, neither on ruby-1.8.6
nor 1.8.7.

Any guesses? Suggestions? Workarounds?





John Carter Phone : (64)(3) 358 6639
Tait Electronics Fax : (64)(3) 359 4632
PO Box 1645 Christchurch Email : (e-mail address removed)
New Zealand

======================================================================

#!/usr/bin/ruby -w
STDOUT.sync = true

require 'socket'


SERVER_PORT = 7272
CLIENT_PORT = 7373

SERVER_HOST = 'localhost'
CLIENT_HOST = 'localhost'

PACKET_LENGTH = 64

SLEEP_TIME = 3 #seconds

MESSAGE = "I say, boy, I resemble that remark!"

class AbstractDaemon

def initialize(to_host, send_port, recv_port)
@send_port = send_port
@recv_port = recv_port
@host = to_host
@recv_socket = UDPSocket.new
print "Listening on port: #{@recv_port}..."
@recv_socket.bind(0, @recv_port)
puts 'ok'
@send_socket = UDPSocket.new
print "Listening on port: #{@send_port}..."
@send_socket.connect(0, @send_port)
puts 'ok'
do_stuff
end

def do_stuff
raise Exception.new("Dummy method not implemented")
end

def send
puts "Sending message: #{MESSAGE}"
@send_socket.syswrite(MESSAGE)
end

def receive
packet,address = *@recv_socket.recvfrom(PACKET_LENGTH)
puts "Received message: #{packet}"
end

def pause
print "Sleeping"
SLEEP_TIME.times do
print '.'
sleep(1)
end
puts ""
end


end

class Server < AbstractDaemon

def initialize
super(CLIENT_HOST, CLIENT_PORT, SERVER_PORT)
end

def do_stuff
while true
receive
send
# pause
end
end

end

class Client < AbstractDaemon

def initialize
super(SERVER_HOST, SERVER_PORT, CLIENT_PORT)
end

def do_stuff
while true
send
receive
# pause
end
end

end

if ARGV[0] == 'server'
Server.new
elsif ARGV[0] == 'client'
Client.new
else
puts "Usage: #{$0} <client | server>"
end

 

[Bill Kelly]

If I have a pair of Win2k Ruby processes bouncing UDP packets back and
forth...

After awhile one of them dies with Errno::ENOTCONN

The code works under Linux but not under Win2k, neither on ruby-1.8.6
nor 1.8.7.

Any guesses? Suggestions? Workarounds?

Replaced connect/syswrite, with send:

--- john_carter_udp_enotconn.orig.rb 2008-09-09 23:27:04.491375000 -0700
+++ john_carter_udp_enotconn.rb 2008-09-09 23:27:50.975750000 -0700
@@ -28,7 +28,6 @@
puts 'ok'
@send_socket = UDPSocket.new
print "Listening on port: #{@send_port}..."
- @send_socket.connect(0, @send_port)
puts 'ok'
do_stuff
end
@@ -39,7 +38,7 @@

def send
puts "Sending message: #{MESSAGE}"
- @send_socket.syswrite(MESSAGE)
+ @send_socket.send(MESSAGE, 0, @host, @send_port)
end

def receive




Hope this helps,

Bill

 

[John Carter]

Replaced connect/syswrite, with send:

I thought, hmm, I'm pretty sure thats what I tried first....

Anyhoo, I'll try your suggestion and...

...it worked!

Hope this helps,

So I went back to the original code and saw we had...
UDPSocket.open.send

Ping! Light goes on! Everytime we do UDPSocket.open we open an fd and
don't close it.

The mystik Errno::ENOTCONN arises because the open failed (silently)
because we had run out of file handles!

Thanks!

John Carter Phone : (64)(3) 358 6639
Tait Electronics Fax : (64)(3) 359 4632
PO Box 1645 Christchurch Email : (e-mail address removed)
New Zealand