file-backward.c - Et program der læser en fil baglæns.

Lektion 10 - slide 13 : 28 Program 1

#include <stdio.h>

#define   MAXSTRING   100

int main(void){
   char   filename[MAXSTRING];
   int    c;
   FILE   *ifp;

   fprintf(stderr, "\nInput a filename:  ");
   scanf("%s", filename);
   ifp = fopen(filename, "r");     
   fseek(ifp, 0, SEEK_END); 
   fseek(ifp, -1, SEEK_CUR);
   while (ftell(ifp) > 0) {
      c = getc(ifp);        
      putchar(c);
      fseek(ifp, -2, SEEK_CUR); 
   }
   /*  The only character that has not been printed
       is the very first character in the file. */

   fseek(ifp, 0, SEEK_SET);
   c = getc(ifp);
   putchar(c);
   return 0;
}