added send and recv builtins

samples/server.noja

@@ -22,6 +22,8 @@ if net.listen(fd, backlog) != 0:
 		return none;
 	}
 
+buffer = newBuffer(16);
+
 while true:
 	{
 		client_addr = {};
@@ -34,5 +36,20 @@ while true:
 		print('client_fd   = ', client_fd, '\n');
 		print('client_addr = {', client_addr, '}\n');
 		
-		# ..continue..
+		do 
+			{
+				n = net.recv(client_fd, buffer, 0);
+
+				if n < 0:
+					print('Warning! Failed to read from socket!\n');
+				else if n == 0:
+					{
+						# Client disconnected.
+					}
+				else
+					{
+						print('Received ', n, ' bytes: ', buffer, '\n');
+					}
+			}
+		while n > 0;
 	}