diplodocus.org Git - nmh/blob - sbr/fdcompare.c

   1
   2 /*
   3  * fdcompare.c -- are two files identical?
   4  *
   5  * $Id$
   6  */
   7
   8 #include <h/mh.h>
   9
  10
  11 int
  12 fdcompare (int fd1, int fd2)
  13 {
  14     register int i, n1, n2, resp;
  15     register char *c1, *c2;
  16     char b1[BUFSIZ], b2[BUFSIZ];
  17
  18     resp = 1;
  19     while ((n1 = read (fd1, b1, sizeof(b1))) >= 0
  20             && (n2 = read (fd2, b2, sizeof(b2))) >= 0
  21             && n1 == n2) {
  22         c1 = b1;
  23         c2 = b2;
  24         for (i = n1 < sizeof(b1) ? n1 : sizeof(b1); i--;)
  25             if (*c1++ != *c2++) {
  26                 resp = 0;
  27                 goto leave;
  28             }
  29         if (n1 < sizeof(b1))
  30             goto leave;
  31     }
  32     resp = 0;
  33
  34 leave: ;
  35     lseek (fd1, (off_t) 0, SEEK_SET);
  36     lseek (fd2, (off_t) 0, SEEK_SET);
  37     return resp;
  38 }