Name: Samantha Krieger
Student number: 53861092

I copied a lot of the socket code from the reference we were given in the assignment outline.
Donahoo and Calvert from their book TCP/IP Sockets in C (http://cs.baylor.edu/~donahoo/practical/CSockets).

The remaining code is all mine. 

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BACKGROUND TO THE ASSIGNMENT
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The purpose of this assignment is to create a simple multi-threaded server. 
The server needs to be written in C using Pthreads. The server should be 
called "mtserver", and it should take two parameters: 
(a) the maximum number of clients (N) that can connect, and 
(b) the server port number.

Details 
The main server thread does the following: 
1. Create a listening socket 
2. Perpetually look, doing the following: 
	a. Accept a new connection from a client 
	b. If the current number of connections is greater than N, immediately terminate 	the connection; else, start a new child 
	thread to respond to queries. 

A child thread should do the following: 
1. Read data from the new connection. 
2. Process the request. There are four types of requests: 
	a. "uptime", returns the integer
	b. "load", returns the integer value of the current number of clients; 
	c. an arbitrary number of digits, which the server sums up and 
	returns; and 
	d. "exit", returns value 0 and goes to Step 4 below. 
	Notice that all returned values are 4 byte integers. 
	e. Anything other than these four types of requests is 
	considered invalid, and a -1 is returned. You should drop the 
	client when it makes more than two consecutive invalid 
	requests. 
3. Return to 1, looking for another request. 
4. Close the connection to the client and terminate the child 
process.