HJFS(8) HJFS(8)
NAME
hjfs - file server maintenance
SYNOPSIS
allow
chatty
create path uid gid perm [lad]
df
disallow
dump
echo [on|off]
halt
newuser name [options]
users
sync
debug-chdeind file [offset value]
debug-deind file
debug-getblk file [blk|start end]
DESCRIPTION
The following commands should be written to the console of
an hjfs(4) file server.
Allow disables permission checking and allows changing file
ownership (see chgrp(1)). This may help in initializing a
file system. Use this with caution.
Chatty enables chatty 9p.
Create creates a file on the current file system. Uid and
gid are names or numbers from /adm/users. Perm is the low 9
bits of the permission mode of the file, in octal. An
optional final l, a, or d creates a locked file, append-only
file, or directory.
Df prints the number of free, used and total
blocks/megabytes. It scans the block table and can be slow
on large hard disks.
Disallow restores permission checking back to normal after a
file system has been initialized.
Dump immediately starts a dump.
Echo expects the argument on or off. On causes all executed
commands to be printed on the system console. Off reverses
the effects of on.
Halt exits the program.
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HJFS(8) HJFS(8)
Newuser requires a name argument. With no options it adds
user name, with group leader name, to /adm/users and makes
the directory /usr/name owned by user and group name. The
options are
: Add a group: add the name to /adm/users but don't
create the directory. By convention, groups are
numbered starting from 10000, users from 0.
newname Rename existing user name to newname.
=leader Change the leader of name to leader. If leader is
missing, remove the existing leader.
+member Add member to the member list of name.
-member Remove existing member from the member list of
name.
After a successful newuser command the file server over-
writes /adm/users to reflect the internal state of the user
table.
Users reads the contents of file /adm/users to initialize
the file server's internal representation of the users
structure.
Sync writes dirty blocks in memory to the magnetic disk
cache.
Note: Debug commands operate on internal data structures;
they are inherently dangerous and can cause file system dam-
age.
Debug-chdeind changes the value of the byte at the specified
offset in the in-memory directory entry and prints the old
value. Dangerous if used carelessly.
Debug-deind requires a file argument. It prints the direc-
tory entry of file.
Debug-getblk prints the physical blocks of file correspond-
ing to the logical block blk or the logical blocks between
start and end.
EXAMPLES
Check disk usage (output appears on the system console).
% echo df >>/srv/hjfs.cmd
SEE ALSO
hjfs(4)
SOURCE
/sys/src/cmd/hjfs
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HJFS(8) HJFS(8)
BUGS
Debug-chdeind should perhaps be less crazy and have a port-
able interface.
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