stdio-common/tst-fdopen.c

   1 /* Test for fdopen bugs.  */
   2
   3 #include <stdio.h>
   4 #include <unistd.h>
   5 #include <fcntl.h>
   6
   7 #define assert(x) \
   8   if (!(x)) \
   9     { \
  10       fputs ("test failed: " #x "\n", stderr); \
  11       retval = 1; \
  12       goto the_end; \
  13     }
  14
  15 char buffer[256];
  16
  17 int
  18 main (int argc, char *argv[])
  19 {
  20   char *name;
  21   FILE *fp = NULL;
  22   int retval = 0;
  23   int fd;
  24
  25   name = tmpnam (NULL);
  26   fp = fopen (name, "w");
  27   assert (fp != NULL)
  28   fputs ("foobar and baz", fp);
  29   fclose (fp);
  30   fp = NULL;
  31
  32   fd = open (name, O_RDONLY);
  33   assert (fd != -1);
  34   assert (lseek (fd, 5, SEEK_SET) == 5);
  35   /* The file position indicator associated with the new stream is set to
  36      the position indicated by the file offset associated with the file
  37      descriptor.  */
  38   fp = fdopen (fd, "r");
  39   assert (fp != NULL);
  40   assert (getc (fp) == 'r');
  41   assert (getc (fp) == ' ');
  42
  43 the_end:
  44   if (fp != NULL)
  45     fclose (fp);
  46   unlink (name);
  47
  48   return retval;
  49 }