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diff --git a/share/man/man5/dir.5 b/share/man/man5/dir.5 new file mode 100644 index 000000000000..c47104344bf8 --- /dev/null +++ b/share/man/man5/dir.5 @@ -0,0 +1,160 @@ +.\" Copyright (c) 1983, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)dir.5 8.3 (Berkeley) 4/19/94 +.\" $FreeBSD$ +.\" +.Dd April 19, 1994 +.Dt DIR 5 +.Os +.Sh NAME +.Nm dir , +.Nm dirent +.Nd directory file format +.Sh SYNOPSIS +.In dirent.h +.Sh DESCRIPTION +Directories provide a convenient hierarchical method of grouping +files while obscuring the underlying details of the storage medium. +A directory file is differentiated from a plain file +by a flag in its +.Xr inode 5 +entry. +It consists of records (directory entries) each of which contains +information about a file and a pointer to the file itself. +Directory entries may contain other directories +as well as plain files; such nested directories are referred to as +subdirectories. +A hierarchy of directories and files is formed in this manner +and is called a file system (or referred to as a file system tree). +.\" An entry in this tree, +.\" nested or not nested, +.\" is a pathname. +.Pp +Each directory file contains two special directory entries; one is a pointer +to the directory itself +called dot +.Ql .\& +and the other a pointer to its parent directory called dot-dot +.Ql \&.. . +Dot and dot-dot +are valid pathnames, however, +the system root directory +.Ql / , +has no parent and dot-dot points to itself like dot. +.Pp +File system nodes are ordinary directory files on which has +been grafted a file system object, such as a physical disk or a +partitioned area of such a disk. +(See +.Xr mount 2 +and +.Xr mount 8 . ) +.Pp +The directory entry format is defined in the file +.In sys/dirent.h +(which should not be included directly by applications): +.Bd -literal +#ifndef _SYS_DIRENT_H_ +#define _SYS_DIRENT_H_ + +#include <machine/ansi.h> + +/* + * The dirent structure defines the format of directory entries returned by + * the getdirentries(2) system call. + * + * A directory entry has a struct dirent at the front of it, containing its + * inode number, the length of the entry, and the length of the name + * contained in the entry. These are followed by the name padded to a 4 + * byte boundary with null bytes. All names are guaranteed null terminated. + * The maximum length of a name in a directory is MAXNAMLEN. + */ + +struct dirent { + __uint32_t d_fileno; /* file number of entry */ + __uint16_t d_reclen; /* length of this record */ + __uint8_t d_type; /* file type, see below */ + __uint8_t d_namlen; /* length of string in d_name */ +#ifdef _POSIX_SOURCE + char d_name[255 + 1]; /* name must be no longer than this */ +#else +#define MAXNAMLEN 255 + char d_name[MAXNAMLEN + 1]; /* name must be no longer than this */ +#endif +}; + +/* + * File types + */ +#define DT_UNKNOWN 0 +#define DT_FIFO 1 +#define DT_CHR 2 +#define DT_DIR 4 +#define DT_BLK 6 +#define DT_REG 8 +#define DT_LNK 10 +#define DT_SOCK 12 +#define DT_WHT 14 + +/* + * Convert between stat structure types and directory types. + */ +#define IFTODT(mode) (((mode) & 0170000) >> 12) +#define DTTOIF(dirtype) ((dirtype) << 12) + +/* + * The _GENERIC_DIRSIZ macro gives the minimum record length which will hold + * the directory entry. This requires the amount of space in struct direct + * without the d_name field, plus enough space for the name with a terminating + * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary. + */ +#define _GENERIC_DIRSIZ(dp) \ + ((sizeof (struct dirent) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3)) + +#ifdef _KERNEL +#define GENERIC_DIRSIZ(dp) _GENERIC_DIRSIZ(dp) +#endif + +#endif /* !_SYS_DIRENT_H_ */ +.Ed +.Sh SEE ALSO +.Xr fs 5 , +.Xr inode 5 +.Sh HISTORY +A +.Nm +file format appeared in +.At v7 . +.Sh BUGS +The usage of the member d_type of struct dirent is unportable as it is +.Fx Ns -specific . +It also may fail on certain file systems, for example the cd9660 file system. |