mkfs - construct a file system
/etc/mkfs special proto
Mkfs constructs a file system by writing on the special file special according to the
directions found in the prototype file proto. The prototype file contains tokens sepa-
rated by spaces or new lines. The first token is the name of a file to be copied onto
block zero as the bootstrap program, see bproc(8). The second token is a number specify-
ing the size of the created file system. Typically it will be the number of blocks on the
device, perhaps diminished by space for swapping. The next token is the number of i-nodes
in the i-list. The next set of tokens comprise the specification for the root file. File
specifications consist of tokens giving the mode, the user-id, the group id, and the ini-
tial contents of the file. The syntax of the contents field depends on the mode.
The mode token for a file is a 6 character string. The first character specifies the type
of the file. (The characters -bcd specify regular, block special, character special and
directory files respectively.) The second character of the type is either u or - to spec-
ify set-user-id mode or not. The third is g or - for the set-group-id mode. The rest of
the mode is a three digit octal number giving the owner, group, and other read, write,
execute permissions, see chmod(1).
Two decimal number tokens come after the mode; they specify the user and group ID's of the
owner of the file.
If the file is a regular file, the next token is a pathname whence the contents and size
If the file is a block or character special file, two decimal number tokens follow which
give the major and minor device numbers.
If the file is a directory, mkfs makes the entries . and .. and then reads a list of
names and (recursively) file specifications for the entries in the directory. The scan is
terminated with the token $.
If the prototype file cannot be opened and its name consists of a string of digits, mkfs
builds a file system with a single empty directory on it. The size of the file system is
the value of proto interpreted as a decimal number. The number of i-nodes is calculated
as a function of the filsystem size. The boot program is left uninitialized.
A sample prototype specification follows:
d--777 3 1
usr d--777 3 1
sh ---755 3 1 /bin/sh
ken d--755 6 1
b0 b--644 3 1 0 0
c0 c--644 3 1 0 0
filsys(5), dir(5), bproc(8)
There should be some way to specify links.