.\"	$NetBSD: fsdb.8,v 1.2 1995/10/08 23:18:08 thorpej Exp $
.\"
.\" Copyright (c) 1995 John T. Kohl
.\" 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. The name of the author may not be used to endorse or promote products
.\"    derived from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR `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 AUTHOR 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.
.\"
.\" $FreeBSD$
.\"
.Dd August 24, 2006
.Dt FSDB 8
.Os
.Sh NAME
.Nm fsdb
.Nd FFS debugging/editing tool
.Sh SYNOPSIS
.Nm
.Op Fl d
.Op Fl f
.Op Fl r
.Ar fsname
.Sh DESCRIPTION
The
.Nm
utility opens
.Ar fsname
(usually a raw disk partition) and runs a command loop
allowing manipulation of the file system's inode data.
You are prompted
to enter a command with
.Ic "fsdb (inum X)>"
where
.Va X
is the currently selected i-number.
The initial selected inode is the
root of the file system (i-number 2).
The command processor uses the
.Xr editline 3
library, so you can use command line editing to reduce typing if desired.
When you exit the command loop, the file system superblock is marked
dirty and any buffered blocks are written to the file system.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl d
Enable additional debugging output (which comes primarily from
.Xr fsck 8 Ns -derived
code).
.It Fl f
Left for historical reasons and has no meaning.
.It Fl r
Open the file system read/only, and disables all commands that would
write to it.
.El
.Sh COMMANDS
Besides the built-in
.Xr editline 3
commands,
.Nm
supports these commands:
.Pp
.Bl -tag -width indent -compact
.It Cm help
Print out the list of accepted commands.
.Pp
.It Cm inode Ar i-number
Select inode
.Ar i-number
as the new current inode.
.Pp
.It Cm back
Revert to the previously current inode.
.Pp
.It Cm clri Ar i-number
Clear
.Ar i-number .
.Pp
.It Cm lookup Ar name
.It Cm cd Ar name
Find
.Ar name
in the current directory and make its inode the current inode.
.Ar Name
may be a multi-component name or may begin with slash to indicate that
the root inode should be used to start the lookup.
If some component
along the pathname is not found, the last valid directory encountered is
left as the active inode.
This command is valid only if the starting inode is a directory.
.Pp
.It Cm active
.It Cm print
Print out the active inode.
.Pp
.It Cm blocks
Print out the block list of the active inode.
Note that the printout can become long for large files, since all
indirect block pointers will also be printed.
.Pp
.It Cm findblk Ar disk block number ...
Find the inode(s) owning the specified disk block(s) number(s).
Note that these are not absolute disk blocks numbers, but offsets from the
start of the partition.
.Pp
.It Cm uplink
Increment the active inode's link count.
.Pp
.It Cm downlink
Decrement the active inode's link count.
.Pp
.It Cm linkcount Ar number
Set the active inode's link count to
.Ar number .
.Pp
.It Cm ls
List the current inode's directory entries.
This command is valid only
if the current inode is a directory.
.Pp
.It Cm rm Ar name
.It Cm del Ar name
Remove the entry
.Ar name
from the current directory inode.
This command is valid only
if the current inode is a directory.
.Pp
.It Cm ln Ar ino Ar name
Create a link to inode
.Ar ino
under the name
.Ar name
in the current directory inode.
This command is valid only
if the current inode is a directory.
.Pp
.It Cm chinum Ar dirslot Ar inum
Change the i-number in directory entry
.Ar dirslot
to
.Ar inum .
.Pp
.It Cm chname Ar dirslot Ar name
Change the name in directory entry
.Ar dirslot
to
.Ar name .
This command cannot expand a directory entry.
You can only rename an
entry if the name will fit into the existing directory slot.
.Pp
.It Cm chtype Ar type
Change the type of the current inode to
.Ar type .
.Ar Type
may be one of:
.Em file ,
.Em dir ,
.Em socket ,
or
.Em fifo .
.Pp
.It Cm chmod Ar mode
Change the mode bits of the current inode to
.Ar mode .
You cannot change the file type with this subcommand; use
.Ic chtype
to do that.
.Pp
.It Cm chflags Ar flags
Change the file flags of the current inode to
.Ar flags .
.Pp
.It Cm chown Ar uid
Change the owner of the current inode to
.Ar uid .
.Pp
.It Cm chgrp Ar gid
Change the group of the current inode to
.Ar gid .
.Pp
.It Cm chgen Ar gen
Change the generation number of the current inode to
.Ar gen .
.Pp
.It Cm btime Ar time
.It Cm mtime Ar time
.It Cm ctime Ar time
.It Cm atime Ar time
Change the creation (birth), modification, change, or access
time (respectively) on the current inode to
.Ar time .
.Ar Time
should be in the format
.Em YYYYMMDDHHMMSS[.nsec]
where
.Em nsec
is an optional nanosecond specification.
If no nanoseconds are specified, the
.Va birthnsec ,
.Va mtimensec ,
.Va ctimensec ,
or
.Va atimensec
field will be set to zero.
Note that
.Cm btime
is available on UFS2 file systems only.
.Pp
.It Cm quit , q , exit , Em <EOF>
Exit the program.
.El
.Sh SEE ALSO
.Xr editline 3 ,
.Xr fs 5 ,
.Xr clri 8 ,
.Xr fsck 8
.Sh HISTORY
The
.Nm
utility uses the source code for
.Xr fsck 8
to implement most of the file system manipulation code.
The remainder of
.Nm
first appeared in
.Nx ,
written by
.An John T. Kohl .
.Pp
.An Peter Wemm
ported it to
.Fx .
.Sh BUGS
Manipulation of ``short'' symlinks has no effect.
In particular, one should not
try changing a symlink's type.
.Pp
You must specify modes as numbers rather than symbolic names.
.Pp
There are a bunch of other things that you might want to do which
.Nm
does not implement.
.Sh WARNING
Use this tool with extreme caution--you can damage an FFS file system
beyond what
.Xr fsck 8
can repair.