The programs in Figure 4.3 and Figure 4.4 are available at www.cdk5.net/ipc. Use them to make a test kit to determine the conditions in which datagrams are sometimes dropped. Hint: the client program should be able to vary the number of messages sent and their size; the server should detect when a message from a particular client is missed.

Exercise 4.4: Use the program in Figure 4.3 to make a client program that repeatedly reads a line of input from the user, sends it to the server in a UDP datagram message, then receives a message from the server. The client sets a timeout on its socket so that it can inform the user when the server does not reply. Test this client program with the server program in Figure 4.4.

Exercise 4.5: The programs in Figure 4.5 and Figure 4.6 are available at www.cdk5.net/ipc. Modify them so that the client repeatedly takes a line of user’s input and writes it to the stream and the server reads repeatedly from the stream, printing out the result of each read. Make a comparison between sending data in UDP datagram messages and over a stream.

Exercise 4.6: Use the programs developed in Exercise 4.5 to test the effect on the sender when the receiver crashes, and vice-versa.

Submission requirements:

• Submit your source code files (not a zip compressed package) and a readme file details instructions about how to compile and execute your code.
• C/C++, Java, and Python are preferred.
  
  Links for figure: http://www.cdk5.net/wp/extra-material/supplementary-material-for-chapter-4