PROLOG | NAME | SYNOPSIS | DESCRIPTION | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

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
       <sys/types.h>.

       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.

APPLICATION USAGE         top

       None.

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.1‐2008 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.1‐2008
       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:

           sizeof(d_name)

       is incorrect; use:

           strlen(d_name)

       instead.

       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.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       sys_types.h(0p)

       The System Interfaces volume of POSIX.1‐2008, 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, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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.unix.org/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                 2013                        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)