A program in Linux contains three processes , parent, first child and second child, The entry is done via the keyboard (the first child) and sends a signal to the parent, the parent in turn sends a signal, that is, the second child, the second child is a counter that is, for example, 10 letters, all signals reach the second child when the second child reaches, for example 10 groves, he sends a signal to the parent to kill the first child And the second The question Convert this logarithm to the Linux C program show the terminate.