Needing help with sockets

[Martin Dion]

Hi

i'm relatively new to python and I need help with a little program i
wrote

What i want to do:

I want to be able to connect on any port on a system and then send and
receive commands, by following the protocol rules.

If I receive data, it must print on the screen.

It asks for data to send in reply to the data received.

Once data is sent, it must look if there is data to receive and if not,
it must ask the user to send an other string.


The problem, is that once data is sent, it goes to the receive data loop
and blocks until it gets data.





I read a little on non-blocking sockets, but i am not sure if it is what
i should look for

I heard about timed sockets (maybe it could work, but i am unsure)

=========================================================================
import socket

remote = raw_input('To wich host:')
port = input('To wich port:')

#remote = "192.168.0.2"
#port = 22

while 1: # entering software main loop

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) # creating
socket
print "\nConnecting to:",remote,":",port


s.connect((remote, port))
print "\nConnected to:",remote,":",port

while 1: #Net main loop

while 1: #receiving data

data = s.recv(1000)
print data
if len(data) < 1000: break #no more data to get so break

toSend = raw_input("Data to Send:")
if toSend == "!QUIT" :break
s.sendall(toSend)


s.close()
del s

 

[Irmen de Jong]

Thank you for your reply, but I have not been able to find good information
about the select module for a client. Do you know a good place to find
tutorials about select module for clients ?

I'm not sure what you mean with 'select module for a client'...
What do you need to know that is not in the module documentation
or the Python socket howto?

Anyway have a look at the following mini example that I whipped up:

-------------
from select import select
from socket import *
import sys

sock=socket(AF_INET, SOCK_STREAM)
sock.connect( ('ftp.xs4all.nl', 21) ) # ftp port

print '>', # prompt

while 1:
ins, outs, exs = select([sys.stdin, sock], [], [])
if sys.stdin in ins:
userline=sys.stdin.readline()
sock.send(userline)
print '>',
if sock in ins:
socketdata=sock.recv(1000) # buffer = 1000
if socketdata:
print socketdata,
else:
break # no more data

-------------

Does this help? If not, please describe in more detail what you
want to achive, what you've already tried and why that didn't work.

Good luck!

--Irmen de Jong