Tue Oct 10 23:08:53 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
[glibc.git] / dirent / dirent.h
blob5b99437301c01f9026ca1b19199f3417f8dd3f8a
1 /* Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public License as
6 published by the Free Software Foundation; either version 2 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If
16 not, write to the, 1992 Free Software Foundation, Inc., 675 Mass Ave,
17 Cambridge, MA 02139, USA. */
20 * POSIX Standard: 5.1.2 Directory Operations <dirent.h>
23 #ifndef _DIRENT_H
25 #define _DIRENT_H 1
26 #include <features.h>
28 __BEGIN_DECLS
30 #include <gnu/types.h>
33 /* Directory entry structure.
35 This structure is laid out identically to the `struct direct' that
36 represents directory entries in the GNU Hurd and in BSD 4.4 (and
37 incidentally, on disk in the Berkeley fast file system). The `readdir'
38 implementations for GNU and BSD know this; you must change them if you
39 change this structure. */
41 struct dirent
43 __ino_t d_fileno; /* File serial number. */
44 unsigned short int d_reclen; /* Length of the whole `struct dirent'. */
45 unsigned char d_type; /* File type, possibly unknown. */
46 unsigned char d_namlen; /* Length of the file name. */
48 /* Only this member is in the POSIX standard. */
49 char d_name[1]; /* File name (actually longer). */
52 #if defined(__USE_BSD) || defined(__USE_MISC)
53 #define d_ino d_fileno /* Backward compatibility. */
54 #endif
56 #ifdef __USE_BSD
57 /* File types for `d_type'. */
58 enum
60 DT_UNKNOWN = 0,
61 DT_FIFO = 1,
62 DT_CHR = 2,
63 DT_DIR = 4,
64 DT_BLK = 6,
65 DT_REG = 8,
66 DT_LNK = 10,
67 DT_SOCK = 12
70 /* Convert between stat structure types and directory types. */
71 #define IFTODT(mode) (((mode) & 0170000) >> 12)
72 #define DTTOIF(dirtype) ((dirtype) << 12)
73 #endif
76 /* This is the data type of directory stream objects.
77 The actual structure is opaque to users. */
78 typedef struct __dirstream DIR;
80 /* Open a directory stream on NAME.
81 Return a DIR stream on the directory, or NULL if it could not be opened. */
82 extern DIR *opendir __P ((__const char *__name));
84 /* Close the directory stream DIRP.
85 Return 0 if successful, -1 if not. */
86 extern int closedir __P ((DIR * __dirp));
88 /* Read a directory entry from DIRP.
89 Return a pointer to a `struct dirent' describing the entry,
90 or NULL for EOF or error. The storage returned may be overwritten
91 by a later readdir call on the same DIR stream. */
92 extern struct dirent *readdir __P ((DIR * __dirp));
94 /* Rewind DIRP to the beginning of the directory. */
95 extern void rewinddir __P ((DIR * __dirp));
97 #if defined(__USE_BSD) || defined(__USE_MISC)
99 /* Return the file descriptor used by DIRP. */
100 extern int dirfd __P ((DIR *__dirp));
102 #if defined (__OPTIMIZE__) && defined (_DIR_dirfd)
103 #define dirfd(dirp) _DIR_dirfd (dirp)
104 #endif
106 #ifndef MAXNAMLEN
107 /* Get the definitions of the POSIX.1 limits. */
108 #include <posix1_lim.h>
110 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'. */
111 #ifdef NAME_MAX
112 #define MAXNAMLEN NAME_MAX
113 #else
114 #define MAXNAMLEN 255
115 #endif
116 #endif
118 #include <gnu/types.h>
119 #define __need_size_t
120 #include <stddef.h>
122 /* Seek to position POS on DIRP. */
123 extern void seekdir __P ((DIR * __dirp, __off_t __pos));
125 /* Return the current position of DIRP. */
126 extern __off_t telldir __P ((DIR * __dirp));
128 /* Scan the directory DIR, calling SELECT on each directory entry.
129 Entries for which SELECT returns nonzero are individually malloc'd,
130 sorted using qsort with CMP, and collected in a malloc'd array in
131 *NAMELIST. Returns the number of entries selected, or -1 on error. */
132 extern int scandir __P ((__const char *__dir,
133 struct dirent ***__namelist,
134 int (*__select) __P ((struct dirent *)),
135 int (*__cmp) __P ((__const __ptr_t,
136 __const __ptr_t))));
138 /* Function to compare two `struct dirent's alphabetically. */
139 extern int alphasort __P ((__const __ptr_t, __const __ptr_t));
142 /* Read directory entries from FD into BUF, reading at most NBYTES.
143 Reading starts at offset *BASEP, and *BASEP is updated with the new
144 position after reading. Returns the number of bytes read; zero when at
145 end of directory; or -1 for errors. */
146 extern __ssize_t __getdirentries __P ((int __fd, char *__buf,
147 size_t __nbytes, __off_t *__basep));
148 extern __ssize_t getdirentries __P ((int __fd, char *__buf,
149 size_t __nbytes, __off_t *__basep));
152 #endif /* Use BSD or misc. */
154 __END_DECLS
156 #endif /* dirent.h */