KFS(4) KFS(4)
NAME
kfs - disk file system
SYNOPSIS
disk/kfs [ -cCrs ] [ -b n ] [ -f file ] [ -n name ] [ -p
perm ] [ -B nbuf ]
DESCRIPTION
Kfs is an old, local user-level file server for a Plan 9
terminal with a disk. It maintains a hierarchical Plan 9
file system on the disk and offers 9P (see intro(5)) access
to it. Kfs begins by checking the file system for consis-
tency, rebuilding the free list, and placing a file descrip-
tor in /srv/name, where name is the service name (default
kfs). If the file system is inconsistent, the user is asked
for permission to ream (q.v.) the disk. The file system is
not checked if it is reamed.
The options are
b n If the file system is reamed, use n byte blocks.
Larger blocks make the file system faster and less
space efficient. 1024 and 4096 are good choices. N
must be a multiple of 512.
c Do not check the file system. C Chatty 9p.
f file Use file as the disk. The default is /dev/sdC0/fs.
n name Use kfs.name as the name of the service.
p perm Use perm as the initial permissions for the command
channel /srv/service.cmd; the default is 660.
r Ream the file system, erasing all of the old data
and adding all blocks to the free list.
s Post file descriptor zero in /srv/service and read
and write protocol messages on file descriptor one.
B Allocate nbuf in-memory file system blocks. The
default is as many as will fit in 10% of memory or
two megabytes, whichever is smaller.
EXAMPLES
Create a file system with service name kfs.local and mount
it on /n/kfs.
% disk/kfs -rb4096 -nlocal
% mount -c /srv/kfs.local /n/kfs
FILES
/dev/sdC0/fs Default file holding blocks.
SOURCE
/sys/src/cmd/disk/kfs
Page 1 Plan 9 (printed 10/30/25)
KFS(4) KFS(4)
SEE ALSO
fossil(4), kfscmd(8), mkfs(8), prep(8), sd(3)
BUGS
For the moment, kfs serves both the old (third edition) and
new (fourth edition) versions of 9P, deciding which to serve
by sniffing the first packet on each connection.
Kfs doesn't allow creating files with component names longer
than 28 bytes.
Page 2 Plan 9 (printed 10/30/25)