summaryrefslogtreecommitdiffstats
path: root/man-pages-posix-2013/man0p/dirent.h.0p
blob: 3df87ce4d737054c63e22ebc7c01dcb4db89cdbe (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
'\" et
.TH dirent.h "0P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"
.SH PROLOG
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.

.SH NAME
dirent.h
\(em format of directory entries
.SH SYNOPSIS
.LP
.nf
#include <dirent.h>
.fi
.SH DESCRIPTION
The internal format of directories is unspecified.
.P
The
.IR <dirent.h> 
header shall define the following type:
.IP "\fBDIR\fR" 8
A type representing a directory stream. The
.BR DIR
type may be an incomplete type.
.P
It shall also define the structure
.BR dirent
which shall include the following members:
.sp
.RS 4
.nf
\fB
ino_t  d_ino       \fRFile serial number.\fR
char   d_name[]    \fRFilename string of entry.\fR
.fi \fR
.P
.RE
.P
The
.IR <dirent.h> 
header shall define the
.BR ino_t
type as described in
.IR <sys/types.h> .
.P
The array
.IR d_name
is of unspecified size, but shall contain a filename of at most
{NAME_MAX}
bytes followed by a terminating null byte.
.P
The following shall be declared as functions and may also be defined as
macros. Function prototypes shall be provided.
.sp
.RS 4
.nf
\fB
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 *);
.fi \fR
.P
.RE
.LP
.IR "The following sections are informative."
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
Information similar to that in the
.IR <dirent.h> 
header is contained in a file
.IR <sys/dir.h> 
in 4.2 BSD and 4.3 BSD. The equivalent in these implementations of
.BR "struct dirent"
from this volume of POSIX.1\(hy2008 is
.BR "struct direct" .
The filename was changed because the name
.IR <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\(hy2008 does not completely
define what is in the structure, so it could be different on some
implementations from
.BR "struct direct" .
.P
The name of an array of
.BR char
of an unspecified size should not be used as an lvalue. Use of:
.sp
.RS 4
.nf
\fB
sizeof(d_name)
.fi \fR
.P
.RE
.P
is incorrect; use:
.sp
.RS 4
.nf
\fB
strlen(d_name)
.fi \fR
.P
.RE
.P
instead.
.P
The array of
.BR char
.IR d_name
is not a fixed size. Implementations may need to declare
.BR "struct dirent"
with an array size for
.IR d_name
of 1, but the actual number of bytes provided matches (or only slightly
exceeds) the length of the filename string.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "\fB<sys_types.h>\fP"
.P
The System Interfaces volume of POSIX.1\(hy2008,
.IR "\fIalphasort\fR\^(\|)",
.IR "\fIclosedir\fR\^(\|)",
.IR "\fIdirfd\fR\^(\|)",
.IR "\fIfdopendir\fR\^(\|)",
.IR "\fIreaddir\fR\^(\|)",
.IR "\fIrewinddir\fR\^(\|)",
.IR "\fIseekdir\fR\^(\|)",
.IR "\fItelldir\fR\^(\|)"
.SH COPYRIGHT
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 .