函数名: putw
功  能: 把一字符或字送到流中
用  法: int putw(int w, FILE *stream);
程序例:

#include <stdio.h>
#include <stdlib.h>

#define FNAME "test.$$$"

int main(void)
{
   FILE *fp;
   int word;

   /* place the word in a file */
   fp = fopen(FNAME, "wb");
   if (fp == NULL)
   {
      printf("Error opening file %s\n", FNAME);
      exit(1);
   }

   word = 94;
   putw(word,fp);
   if (ferror(fp))
       printf("Error writing to file\n");
   else
       printf("Successful write\n");
   fclose(fp);

   /* reopen the file */
   fp = fopen(FNAME, "rb");
   if (fp == NULL)
   {
      printf("Error opening file %s\n", FNAME);
      exit(1);
   }

   /* extract the word */
   word = getw(fp);
   if (ferror(fp))
       printf("Error reading file\n");
   else
       printf("Successful read: word = %d\n", word);

   /* clean up */
   fclose(fp);
   unlink(FNAME);

   return 0;
}