Project 1 (Page 1)

1
Project 1 (Page 1)

• Write a program that meets the following
  specifications. Have a Parent process create two
  child processes, called Child1 and Child2. Then,
  set up a ring between the three processes. Have
  your program use ARGV/ARGC to read two parameters
  into the program called Param1 and Param2.
  Param1 is a UNIX command to be executed such as
  ls l, and Param2 is the name of a data file
  called MY.DAT that does not exist in your
  directory at program start.

2
Project 1 (Page 2)

• Execute your program in the background, and have
  it block at Parent until SIGUSR1 is raised by you
  at the user prompt. When SIGUSR1 is raised, have
  Parent bundle the command, Param1, into a buffer
  called COMMAND and pass it to Child1. Make sure
  neither Child1 nor Child2 can catch SIGUSR1.
  Then have Child1 execute the command and place
  the result into another buffer called RESULT,
  where it is passed to Parent and then over to
  Child2. Then have Child2 enter an infinite loop
  until SIGUSR2 is raised by you at the user
  prompt.

3
Project 1 (Page 3)

• Ensure that only Child2 can catch SIGUSR2. When
  caught, SIGUSR2 raises an interrupt handling
  routine that writes the contents of the RESULT
  buffer to youre MY.DAT file and writes a
  duplicate copy to a data file in the instructors
  account called myoutput_mn, where mn is a magic
  number that I assign to your project group. For
  example, if I assign you mn 14, you will write
  your output to
• /usr/faculty/Hilzer/csci640/project1/myoutput_14

4
Project 1 (Page 4)

• During execution of the program, write the
  activities of each process to standard error so
  that it is clear by reading the screen what each
  process is doing. Ensure that all processes
  terminate normally leaving no zombies.