dirent.h(3)                POSIX Programmer's Manual               dirent.h(3)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       dirent.h -- format of directory entries

SSYYNNOOPPSSIISS
       #include <dirent.h>

DDEESSCCRRIIPPTTIIOONN
       The internal format of directories is unspecified.

       The _<_d_i_r_e_n_t_._h_> header shall define the following type:

       DDIIRR     A type representing a directory stream. The DDIIRR type may be an
               incomplete type.

       It shall also define the structure ddiirreenntt which shall include the
       following members:


           ino_t  d_ino       File serial number.
           char   d_name[]    Filename string of entry.

       The _<_d_i_r_e_n_t_._h_> header shall define the iinnoo__tt type as described in
       _<_s_y_s_/_t_y_p_e_s_._h_>.

       The array _d___n_a_m_e is of unspecified size, but shall contain a filename
       of at most {NAME_MAX} bytes followed by a terminating null byte.

       The following shall be declared as functions and may also be defined as
       macros. Function prototypes shall be provided.


           int            alphasort(const struct dirent **, const struct dirent **);
           int            closedir(DIR *);
           int            dirfd(DIR *);
           DIR           *fdopendir(int);
           DIR           *opendir(const char *);
           struct dirent *readdir(DIR *);
           int            readdir_r(DIR *restrict, struct dirent *restrict,
                              struct dirent **restrict);
           void           rewinddir(DIR *);
           int            scandir(const char *, struct dirent ***,
                              int (*)(const struct dirent *),
                              int (*)(const struct dirent **,
                              const struct dirent **));
           void           seekdir(DIR *, long);
           long           telldir(DIR *);

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       None.

RRAATTIIOONNAALLEE
       Information similar to that in the _<_d_i_r_e_n_t_._h_> header is contained in a
       file _<_s_y_s_/_d_i_r_._h_> in 4.2 BSD and 4.3 BSD. The equivalent in these
       implementations of ssttrruucctt ddiirreenntt from this volume of POSIX.1-2017 is
       ssttrruucctt ddiirreecctt.  The filename was changed because the name _<_s_y_s_/_d_i_r_._h_>
       was also used in earlier implementations to refer to definitions
       related to the older access method; this produced name conflicts. The
       name of the structure was changed because this volume of POSIX.1-2017
       does not completely define what is in the structure, so it could be
       different on some implementations from ssttrruucctt ddiirreecctt.

       The name of an array of cchhaarr of an unspecified size should not be used
       as an lvalue. Use of:


           sizeof(d_name)

       is incorrect; use:


           strlen(d_name)

       instead.

       The array of cchhaarr _d___n_a_m_e is not a fixed size. Implementations may need
       to declare ssttrruucctt ddiirreenntt with an array size for _d___n_a_m_e of 1, but the
       actual number of bytes provided matches (or only slightly exceeds) the
       length of the filename string.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       <<ssyyss__ttyyppeess..hh>>

       The System Interfaces volume of POSIX.1-2017, _a_l_p_h_a_s_o_r_t(), _c_l_o_s_e_d_i_r(),
       _d_i_r_f_d(), _f_d_o_p_e_n_d_i_r(), _r_e_a_d_d_i_r(), _r_e_w_i_n_d_d_i_r(), _s_e_e_k_d_i_r(), _t_e_l_l_d_i_r()

CCOOPPYYRRIIGGHHTT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  In the event of any discrepancy between this version and the
       original IEEE and The Open Group Standard, the original IEEE and The
       Open Group Standard is the referee document. The original Standard can
       be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                          dirent.h(3)
