# Exercise #2

Create two C programs, `listen.c` and `say.c` that replicate the functionality
of the two bash scripts as closely as possible. Things you may need to know to
complete this assignment are:

- The system calls: `fork`(2), `execve`(2)/`execlp`(3) and `wait`(2)/`waitpid`(2)
  to fork and exec the clear command.
- The C library function `mkfifo`(3) or the system call `mknod`(2) and system
  call `unlink`(2) to make the named pipe and later remove it.
- The system call `chmod`(2) to set the permissions on the fifo
- The system calls `access`(2) and/or `stat`(2) to test for the existence of
  the named pipe. (The `if [ -p "$pf" ]; then`... test)
- The `signal`(2)/`sigaction`(2) to handle trapping the the Ctrl-C in the
  listen program.