第 13 章 文件输入/输出 （标准I/O）

 /*--------------------------
     count.c -- 使用标准 I/O
 --------------------------*/

 #include <stdio.h>
 #include <stdlib.h>        //提供 exit() 函数原型

 int main(int argc, char *argv[])
 {
     int ch;        //读取文件时，储存每个字符的地方
     FILE *fp;    //文件指针
     unsigned long count = ;

     if (argc != )
     {
         printf("Usage: %s filename\n", argv[]);
         exit(EXIT_FAILURE);
     }

     if (NULL == (fp = fopen(argv[], "r")))
     {
         printf("Can't open %s\n", argv[]);
         exit(EXIT_FAILURE);
     }

     while (EOF != (ch = getc(fp)))
     {
         putc(ch, stdout);        //同 putchar(ch)
         ++count;
     }

     fclose(fp);
     printf("File %s has %lu characters\n", argv[], count);

     return ;
 }

count.c