mynice.c

LINUX C编程实战这本书附带光盘的原代码

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/resource.h>
#include <sys/wait.h>

int main(void)
{
	pid_t	pid;
	int 		stat_val = 0;
	int 		oldpri, newpri;

	printf("nice study\n");

	pid = fork();
	switch(pid) {
		case 0:
			printf("Child is running,CurPid is %d, 
				ParentPid is %d\n", pid, getppid());
			
			oldpri = getpriority(PRIO_PROCESS,0);
			printf("Old priority = %d\n",oldpri);
			
			newpri = nice(2);
			printf("New priority = %d\n",newpri);
		
			exit(0);
		case -1:
			perror("Process creation failed\n");
			break;
		default:
			printf("Parent is running,ChildPid is %d, 
				ParentPid is %d\n", pid, getpid());
			break;	
	}

	wait(&stat_val);
	exit(0);
}