NAME
mtree - format of mtree dir hierarchy files
DESCRIPTION
The mtree format is a textual format that describes a collection of
filesystem objects. Such files are typically used to create or verify
directory hierarchies.
General Format
An mtree file consists of a series of lines, each providing information
about a single filesystem object. Leading whitespace is always ignored.
When encoding file or pathnames, any backslash character or character
outside of the 95 printable ASCII characters must be encoded as a a
backslash followed by three octal digits. When reading mtree files, any
appearance of a backslash followed by three octal digits should be
converted into the corresponding character.
Each line is interpreted independently as one of the following types:
Signature The first line of any mtree file must begin with “#mtree”.
If a file contains any full path entries, the first line
should begin with “#mtree v2.0”, otherwise, the first line
should begin with “#mtree v1.0”.
Blank Blank lines are ignored.
Comment Lines beginning with # are ignored.
Special Lines beginning with / are special commands that influence
the interpretation of later lines.
Relative If the first whitespace-delimited word has no / characters,
it is the name of a file in the current directory. Any
relative entry that describes a directory changes the current
directory.
dot-dot As a special case, a relative entry with the filename ..
changes the current directory to the parent directory.
Options on dot-dot entries are always ignored.
Full If the first whitespace-delimited word has a / character
after the first character, it is the pathname of a file
relative to the starting directory. There can be multiple
full entries describing the same file.
Some tools that process mtree files may require that multiple lines
describing the same file occur consecutively. It is not permitted for
the same file to be mentioned using both a relative and a full file
specification.
Special commands
Two special commands are currently defined:
/set This command defines default values for one or more keywords.
It is followed on the same line by one or more whitespace-
separated keyword definitions. These definitions apply to
all following files that do not specify a value for that
keyword.
/unset This command removes any default value set by a previous /set
command. It is followed on the same line by one or more
keywords separated by whitespace.
Keywords
After the filename, a full or relative entry consists of zero or more
whitespace-separated keyword definitions. Each such definition consists
of a key from the following list immediately followed by an ’=’ sign and
a value. Software programs reading mtree files should warn about
unrecognized keywords.
Currently supported keywords are as follows:
cksum The checksum of the file using the default algorithm
specified by the cksum(1) utility.
contents The full pathname of a file that holds the contents of this
file.
flags The file flags as a symbolic name. See chflags(1) for
information on these names. If no flags are to be set the
string “none” may be used to override the current default.
gid The file group as a numeric value.
gname The file group as a symbolic name.
ignore Ignore any file hierarchy below this file.
link The target of the symbolic link when type=link.
md5 The MD5 message digest of the file.
md5digest A synonym for md5.
mode The current file’s permissions as a numeric (octal) or
symbolic value.
nlink The number of hard links the file is expected to have.
nochange Make sure this file or directory exists but otherwise ignore
all attributes.
ripemd160digest
The RIPEMD160 message digest of the file.
rmd160 A synonym for ripemd160digest.
rmd160digest
A synonym for ripemd160digest.
sha1 The FIPS 160-1 (“SHA-1”) message digest of the file.
sha1digest A synonym for sha1.
sha256 The FIPS 180-2 (“SHA-256”) message digest of the file.
sha256digest
A synonym for sha256.
size The size, in bytes, of the file.
time The last modification time of the file.
type The type of the file; may be set to any one of the following:
block block special device
char character special device
dir directory
fifo fifo
file regular file
link symbolic link
socket socket
uid The file owner as a numeric value.
uname The file owner as a symbolic name.
SEE ALSO
cksum(1), find(1), mtree(8)
BUGS
The FreeBSD implementation of mtree does not currently support the mtree
2.0 format. The requirement for a “#mtree” signature line is new and not
yet widely implemented.
HISTORY
The mtree utility appeared in 4.3BSD-Reno. The MD5 digest capability was
added in FreeBSD 2.1, in response to the widespread use of programs which
can spoof cksum(1). The SHA-1 and RIPEMD160 digests were added in
FreeBSD 4.0, as new attacks have demonstrated weaknesses in MD5. The
SHA-256 digest was added in FreeBSD 6.0. Support for file flags was
added in FreeBSD 4.0, and mostly comes from NetBSD. The “full” entry
format was added by NetBSD.