Please write the program. For the communication programming of the linuxc process, thank you for your help.

Please write the program. For more information about the communication programming of the linuxc process, thank you-general Linux technology-Linux technology and application. For more information, see the following. Write a program and create two sub-processes in the main process. sub-process 1 performs an empty loop and continuously outputs "Hello, I am subprogram 1 !" String, sub-process 2 for an empty loop, non-stop output "Hello, I am subprogram 2 !" String. After the main process is sleep for a period of time, the child process ends in the main process, and then the main process also exits.
Note: You must control the concurrency of sub-processes to prevent the output results of the two processes from being intertwined.