The C program that accepts a positive integer n as a parameter. When executed, the process spawns child processes each executing a copy of the same program, as following.The parameter of 2nd child can not work correctly. Someone help out please. Or is there any better ideas(like recursive)? if n > 1, the process spawns two children with parameters n-1 and n-2; if n <= 1, the process spawns no child processes. Part of my work is as following: #include <stdio.h> #include <stdlib.h> #include <signal.h> #include <sys/wait.h> #include <sys/types.h> #include <unistd.h> #include <setjmp.h> sigjmp_buf position; int main(int argc, char *argv[]) { int num; pid_t pid, pid1; char buffer[512]; static struct sigaction act; void goback(void); if (argc != 2) { printf("Usage: spanwner [posi_num]\n"); exit(1); } /* get value of pid from the parameter */ num = strtol(argv[1], NULL, 0); if (num < 1) { printf("Usage: spanwner [posi_num]\n"); exit(1); } if(sigsetjmp(position,1) == 0) { act.sa_handler = goback; sigaction(SIGINT, &act, NULL); } if(num > 1) { if ((pid = fork()) == 0 ) { pid = getpid(); printf("\nParameter of process %d is %d\n", pid, num-1); kill(pid, SIGINT); if ((pid1 = fork()) == 0 ) { pid1 = getpid(); printf("\nParameter of processss %d is %d\n", pid1, num-2); kill(pid1, SIGINT); } } else if (pid > 0) { wait((int *)0); exit(0); } else printf("forking fails!!"); } exit(0); } void goback(void) { siglongjmp(position,1); }