DETECT if a CLIENT still exits

[Zaafir Barahim]

hi, i have a server that periodically wait for clients to send files and there are many clients that just send text file to the server. Now i want to write a code that enable the server to know if a client still exits as each clients send a file at a specific interval of time and if one client has not send any file for example in 2minutes then the server must know that the client is down and do the action that i want when a client is down.PLEASE i NEED HELP to write the code to do this. HELP ME!!!.Thanks in advance.

[Joe Ess]

This is commonly called a "heartbeat". You code your client and server to exchange a message at regular intervals and if one does not receive the message at the expected time some action is taken. Why don't you take a swing at it and we'll help you along if you have problems?