[Tutor] Re: socket question

alan.gauld@bt.com alan.gauld@bt.com
Mon Dec 23 11:55:31 2002


> Let me clarify.  I'm looking for a server to "ping" me.  

> to send any data at all.  Just a blank tcp packet 

Umm, if its literally ping then you won't get tcp at all. 
ping doesn't use tcp it uses another IP protocol called ICMP.
It sends an ECHO_REQUEST and you have to respond with an 
ECHO_RESPONSE. (See man ping & man icmp)

> python?  Do I have to use server mode (listen() instead of 
> receive()) ?

If the other box is contacting you then you need to be 
listening for the right protocol in the right place.

Alan g.