rewinddir.c 737 B

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  1. /*
  2. rewinddir -- rewind a directory stream
  3. last edit: 25-Apr-1987 D A Gwyn
  4. This is not simply a call to seekdir(), because seekdir()
  5. will use the current buffer whenever possible and we need
  6. rewinddir() to forget about buffered data.
  7. */
  8. #include <errno.h>
  9. #include <sys/errno.h>
  10. #include <sys/types.h>
  11. #include <dirent.h>
  12. extern off_t _lseek(int d, int offset, int whence);
  13. #ifndef NULL
  14. #define NULL 0
  15. #endif
  16. #ifndef SEEK_SET
  17. #define SEEK_SET 0
  18. #endif
  19. void
  20. rewinddir(register DIR *dirp)
  21. {
  22. if ( dirp == NULL || dirp->dd_buf == NULL )
  23. {
  24. errno = EFAULT;
  25. return; /* invalid pointer */
  26. }
  27. dirp->dd_loc = dirp->dd_size = 0; /* invalidate buffer */
  28. (void)_lseek( dirp->dd_fd, (off_t)0, SEEK_SET ); /* may set errno */
  29. }