[Tutor] changing a variable over simple network (with pyOpenGL)

[Michael Shulman]

Hello,

I am trying to write a very simple py-opengl program pair causing a 
variable in each program to be changed by the other.  I am able to open 
a command window in which I manually assign a value to the variable, but 
I cannot seem to implement  the udp/ip information I wish to send into a 
function which I can call at will.  I have tried updating the function 
through both a cyclic update function, and the keyboard (keyboard is 
preferred, but I tried eliminating it to see if that was the 
incompatibility).   I do not list any coding for the receiving program, 
since it works perfectly with the above code, and is probably correct.

Currently, the program crashes when I press the assigned key.  I can't 
tell if the issue here is python, or OpenGL, but any help would be very 
greatly appreciated!!!

##########Here is what DOES work:
#############################

from socket import *
udpsock = socket(AF_INET, SOCK_DGRAM)
udpsock.bind(('', 0))
udpsock.connect(('localhost', 4550))

try:

    while True:
        s = raw_input('command> ')
        udpsock.send(s)

except EOFError: pass
###########################

#############This is what DOES NOT work:
##############################
from socket import *
udpsock = socket(AF_INET, SOCK_DGRAM)
udpsock.bind(('', 0))
udpsock.connect(('localhost', 4550))
R = 0
def datasender():
    global R
    try:

        while True:           
                s = input(R)
                udpsock.send(s)

    except EOFError: pass

def keyboard(key, x, y):  #######the keyboard and window OpenGL calls 
are not mentioned here, but included properly in the program (they work 
with everything except this)
    global R
    if key == 'k':  #####key is arbitrary, I have also tried with 
"special keys" as defined by glut
          R = R + .01
          datasender()

################################