使用getrlimit控制进程使用系统CPU

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/resource.h>
#include <signal.h>

void sigxcpu_handler(int signum)
{
	printf ("SIGXCPU Received!\n");

	//可以在这里就退出进程 exit(1);
}

void sigkill_handler(int signum)
{
	printf ("SIGKILL received!\n");
}

int main(void)
{
	signal(SIGXCPU, sigxcpu_handler);

	//无效的,kill信号不允许自定义
	signal(SIGKILL, sigkill_handler);

	struct rlimit rl;
	int ret = getrlimit (RLIMIT_CPU, &rl);
	if (ret == -1)
	{
		printf("Failed to getrlimit!\n");
		exit(-1);
	}

	//进程使用cpu时间达到rlim_cur时，操作系统向进程发送SIGXCPU信号，如果进程未终止，则之后每秒发送一次
	rl.rlim_cur = 1;

	//进程使用CPU时间达到rlim_max时，操作系统向进程发送SIGKILL信号，终止进程
	rl.rlim_max = 5;

	ret = setrlimit (RLIMIT_CPU, &rl);
	if (ret == -1)
	{
		printf("Failed to set limit.\n");
		exit(-1);
	}

	while (1)
		;

	return 0;
}