test9_9.txt

Linux下的C语言编程

#include <sys/types.h>
#include <sys/wait.h>
#include <stdio.h>
#include <stdlib.h>

int main(void)
{
    	int status;

    	if((status=system(NULL))<0)
    	{
        	printf("system error! \n");
        	exit(0);
    	}
    	printf("exit status=%d\n", status);
	
    	if((status=system("data"))<0)
    	{
        	printf("system error! \n");
        	exit(0);
    	}
    	printf("exit status=%d\n", status);

    	if((status=system("invalidcommand"))<0)
    	{
        	printf("system error! \n");
        	exit(0);
    	}
	printf("exit status=%d.\n", status);

	if((status=system("who;exit 44"))<0)
	{
        	printf("system error! \n");
        	exit(0);
	}
	printf("exit status=%d. \n", status);

	exit(0);
}