Task: Anon Pipes

Navigate to labs/lab-09/tasks/anon-pipes and run make to generate the support/ folder. In this exercise, you’ll implement client-server communication between a parent and a child process using an anonymous pipe. The parent will act as the sender, while the child acts as the receiver, with both processes sharing messages through the pipe. Since pipes are unidirectional, each process should close the end of the pipe it does not use.

  1. Inside the tests/ directory, you will need to run checker.sh. The output for a successful implementation should look like this:
./checker.sh
make: Nothing to be done for 'all'.

Test for short string ........... PASSED
Test for long string  ........... PASSED

  1. Use the pipe() syscall to create the pipe. Remember, the first file descriptor (fds[0]) is the read end, and the second (fds[1]) is the write end, similar to how stdin and stdout are represented by file descriptors 0 and 1.

    Hint: Use exit to end the program.

    Quiz: Discover why you cannot use either end of the pipe for reading or writing

  2. Solve the TODOs in parent_loop and child_loop so that the application stops on exit. Ensure each process closes the its pipe end before exiting to prevent indefinite blocking.

    Why is closing the pipe ends important?

    The child process checks for the end of communication by reading from the pipe and checking for EOF, which occurs when the write end is closed. Without closing the write end, the child will block indefinitely in read(). As for the parent, it will block indefinitely in wait().