TELLDIR(3)                                                              Linux Programmer's Manual                                                             TELLDIR(3)

NAME
       telldir - return current location in directory stream

SYNOPSIS
       #include <dirent.h>

       long telldir(DIR *dirp);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       telldir():
           _XOPEN_SOURCE
              || /* Glibc since 2.19: */ _DEFAULT_SOURCE
              || /* Glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION
       The telldir() function returns the current location associated with the directory stream dirp.

RETURN VALUE
       On success, the telldir() function returns the current location in the directory stream.  On error, -1 is returned, and errno is set to indicate the error.

ERRORS
       EBADF  Invalid directory stream descriptor dirp.

ATTRIBUTES
       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │Interface                                                                                                                             │ Attribute     │ Value   │
       ├──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │telldir()                                                                                                                             │ Thread safety │ MT-Safe │
       └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, 4.3BSD.

NOTES
       In glibc up to version 2.1.1, the return type of telldir() was off_t.  POSIX.1-2001 specifies long, and this is the type used since glibc 2.1.2.

       In  early  filesystems, the value returned by telldir() was a simple file offset within a directory.  Modern filesystems use tree or hash structures, rather than
       flat tables, to represent directories.  On such filesystems, the value returned by telldir() (and used internally by readdir(3)) is a "cookie" that  is  used  by
       the  implementation to derive a position within a directory.  Application programs should treat this strictly as an opaque value, making no assumptions about its
       contents.

SEE ALSO
       closedir(3), opendir(3), readdir(3), rewinddir(3), scandir(3), seekdir(3)

                                                                               2021-03-22                                                                     TELLDIR(3)