stdio-common/tst-ungetc.c

   1 /* Test for ungetc bugs.  */
   2
   3 #include <stdio.h>
   4
   5 #define assert(x) \
   6   if (!(x)) \
   7     { \
   8       fputs ("test failed: " #x "\n", stderr); \
   9       retval = 1; \
  10       goto the_end; \
  11     }
  12
  13 int
  14 main (int argc, char *argv[])
  15 {
  16   char *name;
  17   FILE *fp = NULL;
  18   int retval = 0;
  19   int c;
  20
  21   name = tmpnam (NULL);
  22   fp = fopen (name, "w");
  23   assert (fp != NULL)
  24   fputs ("bl", fp);
  25   fclose (fp);
  26   fp = NULL;
  27
  28   fp = fopen (name, "r");
  29   assert (fp != NULL)
  30   assert (getc (fp) != EOF);
  31   assert ((c = getc (fp)) != EOF);
  32   assert (getc (fp) == EOF);
  33   assert (ungetc (c, fp) == c);
  34   assert (feof (fp) == 0);
  35
  36 the_end:
  37   if (fp != NULL)
  38     fclose (fp);
  39   unlink (name);
  40
  41   return retval;
  42 }