#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int main(int argc,char *argv[])
{
FILE *src;
char *buf=NULL;
size_t n=0;
if(argc < 2){
fprintf(stderr,"Usage...\n");
exit(1);
}
src=fopen(argv[1],"r");
if(src == NULL){
perror("fopen():");
exit(1);
}
while(1)
{
if(getline(&buf, &n, src) < 0)
//從src文件中讀取一行寫到buf裏面，n獲取到所需內存大小
break;
printf("%d size = %d\n",strlen(buf),n);
}
fclose(src);
exit(0);
}