This section describes how to reread parts of a directory that you have already read from an open directory stream. All the symbols are declared in the header file dirent.h.
void rewinddir (DIR *dirstream) ¶Preliminary: | MT-Safe | AS-Unsafe lock | AC-Unsafe lock | See POSIX Safety Concepts.
The rewinddir function is used to reinitialize the directory
stream dirstream, so that if you call readdir it
returns information about the first entry in the directory again. This
function also notices if files have been added or removed to the
directory since it was opened with opendir. (Entries for these
files might or might not be returned by readdir if they were
added or removed since you last called opendir or
rewinddir.)
For example, it is recommended to call rewinddir followed by
readdir to check if a directory is empty after listing it with
readdir and deleting all encountered files from it.
long int telldir (DIR *dirstream) ¶Preliminary: | MT-Safe | AS-Unsafe heap/bsd lock/bsd | AC-Unsafe mem/bsd lock/bsd | See POSIX Safety Concepts.
The telldir function returns the file position of the directory
stream dirstream. You can use this value with seekdir to
restore the directory stream to that position.
Using the the telldir function is not recommended.
The value returned by telldir may not be compatible with the
d_off field in struct dirent, and cannot be used with the
lseek function. The returned value may not unambiguously
identify the position in the directory stream.
void seekdir (DIR *dirstream, long int pos) ¶Preliminary: | MT-Safe | AS-Unsafe heap/bsd lock/bsd | AC-Unsafe mem/bsd lock/bsd | See POSIX Safety Concepts.
The seekdir function sets the file position of the directory
stream dirstream to pos. The value pos must be the
result of a previous call to telldir on this particular stream;
closing and reopening the directory can invalidate values returned by
telldir.
Using the the seekdir function is not recommended. To seek to
the beginning of the directory stream, use rewinddir.