#include<stdio.h>
#include<error.h>
int main()
{
FILE *fp;
char *str;
int sum=0,i=0,j=0;
char a[20]={'\0'};
fp=fopen("/etc/passwd","rb");
if(fp==NULL)
{
perror("read the passwd file error");
exit(1);
}
while(fgets(str,1024,fp)!=NULL)
{
sum=sum+1;
j=0;
i=0;
while(str[i]!='\0')
{
if(str[i]==':')
break;
a[j++]=str[i++];
}
printf ("the sum %d,account user is :%s",sum,a);
}
}