1  #include <stdio.h>
       2  #include <sys/types.h>
       3  
       4  
       5  static int
       6  check (FILE *fp, off_t o)
       7  {
       8    int result = 0;
       9    if (feof (fp))
      10      {
      11        puts ("feof !");
      12        result = 1;
      13      }
      14    if (ferror (fp))
      15      {
      16        puts ("ferror !");
      17        result = 1;
      18      }
      19    if (ftello (fp) != o)
      20      {
      21        printf ("position = %lu, not %lu\n", (unsigned long int) ftello (fp),
      22  	      (unsigned long int) o);
      23        result = 1;
      24      }
      25    return result;
      26  }
      27  
      28  
      29  static int
      30  do_test (void)
      31  {
      32    FILE *fp = tmpfile ();
      33    if (fp == NULL)
      34      {
      35        puts ("tmpfile failed");
      36        return 1;
      37      }
      38    if (check (fp, 0) != 0)
      39      return 1;
      40  
      41    puts ("going to write");
      42    if (fputs ("hello", fp) == EOF)
      43      {
      44        puts ("fputs failed");
      45        return 1;
      46      }
      47    if (check (fp, 5) != 0)
      48      return 1;
      49  
      50    puts ("going to rewind");
      51    rewind (fp);
      52    if (check (fp, 0) != 0)
      53      return 1;
      54  
      55    puts ("going to read char");
      56    int c = fgetc (fp);
      57    if (c != 'h')
      58      {
      59        printf ("read %c, not %c\n", c, 'h');
      60        return 1;
      61      }
      62    if (check (fp, 1) != 0)
      63      return 1;
      64  
      65    puts ("going to put back");
      66    if (ungetc (' ', fp) == EOF)
      67      {
      68        puts ("ungetc failed");
      69        return 1;
      70      }
      71    if (check (fp, 0) != 0)
      72      return 1;
      73  
      74    puts ("going to write again");
      75    if (fputs ("world", fp) == EOF)
      76      {
      77        puts ("2nd fputs failed");
      78        return 1;
      79      }
      80    if (check (fp, 5) != 0)
      81      return 1;
      82  
      83    puts ("going to rewind again");
      84    rewind (fp);
      85    if (check (fp, 0) != 0)
      86      return 1;
      87  
      88    if (fclose (fp) != 0)
      89      {
      90        puts ("fclose failed");
      91        return 1;
      92      }
      93  
      94    return 0;
      95  }
      96  
      97  #define TEST_FUNCTION do_test ()
      98  #include "../test-skeleton.c"