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recvall corollary to socket.sendall (Python recipe) by John Nielsen
ActiveState Code (http://code.activestate.com/recipes/213239/)

Getting data back from a socket is problematic, because you do no know when it has finished. You'd either need to specify the number of bytes transferred or have some delimeter logic. The function recvall is useful in the case where you do not have knowledge about either or are too busy or lazy to think about it.

Python, 32 lines
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import time,socket

def recvall(the_socket,timeout=''):
    #setup to use non-blocking sockets
    #if no data arrives it assumes transaction is done
    #recv() returns a string
    the_socket.setblocking(0)
    total_data=[];data=''
    begin=time.time()
    if not timeout:
        timeout=1
    while 1:
        #if you got some data, then break after wait sec
        if total_data and time.time()-begin>timeout:
            break
        #if you got no data at all, wait a little longer
        elif time.time()-begin>timeout*2:
            break
        wait=0
        try:
            data=the_socket.recv(4096)
            if data:
                total_data.append(data)
                begin=time.time()
                data='';wait=0
            else:
                time.sleep(0.1)
        except:
            pass
        #When a recv returns 0 bytes, other side has closed
    result=''.join(total_data)
    return result

recvall uses non-blocking sockets and keeps on looking for data until data has not arrived for the timeout amount of time.