Introduction - If you have any usage issues, please Google them yourself
1. Requires the use of fork (), wait (), pipe (), read (), write () and execve () system call such as multi-process programs. 2. Two processes to complete a procedure, the two processes of two procedures, a procedure the procedure the three processes. 3. Operation results in different situations, understanding the process of Linux systems scheduling, concurrent execution of the process and the relationship between parent and child (code segment, data segment between.)