dirent.h(0p) — Linux manual page


dirent.h(0P)            POSIX Programmer's Manual           dirent.h(0P)

PROLOG         top

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

NAME         top

       dirent.h — format of directory entries

SYNOPSIS         top

       #include <dirent.h>

DESCRIPTION         top

       The internal format of directories is unspecified.

       The <dirent.h> header shall define the following type:

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

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

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

       The <dirent.h> header shall define the ino_t type as described in

       The array d_name 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 *);

       The following sections are informative.



RATIONALE         top

       Information similar to that in the <dirent.h> header is contained
       in a file <sys/dir.h> in 4.2 BSD and 4.3 BSD. The equivalent in
       these implementations of struct dirent from this volume of
       POSIX.1‐2017 is struct direct.  The filename was changed because
       the name <sys/dir.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 struct direct.

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


       is incorrect; use:



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



SEE ALSO         top


       The System Interfaces volume of POSIX.1‐2017, alphasort(3p),
       closedir(3p), dirfd(3p), fdopendir(3p), readdir(3p),
       rewinddir(3p), seekdir(3p), telldir(3p)

COPYRIGHT         top

       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(0P)

Pages that refer to this page: alphasort(3p)closedir(3p)dirfd(3p)fdopendir(3p)readdir(3p)rewinddir(3p)seekdir(3p)telldir(3p)