You can’t do this without some kind of network, its required for the computers to communicate with each other. If you don’t have internet access, then bring along a router and assign the server an ip address and assign the client an ip address. Then you could access the server via its IP address (this is what really happens anyway on the internet). If you lack a router, and you have two laptops, you could try an ad hoc network.
One computer running a web server (the one with mysql), both computers with PHP installed and connecting to a network (this does not have to be connected to the internet), and then you would create a server and client (the server being on the web server) in PHP.
You can’t do this without some kind of network, its required for the computers to communicate with each other. If you don’t have internet access, then bring along a router and assign the server an ip address and assign the client an ip address. Then you could access the server via its IP address (this is what really happens anyway on the internet). If you lack a router, and you have two laptops, you could try an ad hoc network.
You need at the bare minimum:
One computer running a web server (the one with mysql), both computers with PHP installed and connecting to a network (this does not have to be connected to the internet), and then you would create a server and client (the server being on the web server) in PHP.
http://www.hotscripts.com/category/php/scripts-programs/chat-scripts/
HTH