usr/src/man/man1m/fsdb_ufs.1m

'\" te
.\"  Copyright (c) 1988 Regents of the University
.\" of California.  All rights reserved.  Copyright (c) 2003 Sun Microsystems,
.\" Inc.  All Rights Reserved.
.TH FSDB_UFS 1M "Apr 14, 2003"
.SH NAME
fsdb_ufs \- ufs file system debugger
.SH SYNOPSIS
.LP
.nf
\fBfsdb\fR \fB-F\fR ufs [\fIgeneric_options\fR] [\fIspecific_options\fR] \fIspecial\fR
.fi

.SH DESCRIPTION
.LP
The \fBfsdb_ufs\fR command is an interactive tool that can be used to patch up
a damaged \fBUFS\fR file system. It has conversions to translate block and
i-numbers into their corresponding disk addresses. Also included are mnemonic
offsets to access different parts of an inode. These greatly simplify the
process of correcting control block entries or descending the file system tree.
.sp
.LP
\fBfsdb\fR contains several error-checking routines to verify inode and block
addresses. These can be disabled if necessary by invoking \fBfsdb\fR with the
\fB-o\fR option or by the use of the \fBo\fR command.
.sp
.LP
\fBfsdb\fR reads a block at a time and will therefore work with raw as well as
block \fBI/O\fR devices. A buffer management routine is used to retain commonly
used blocks of data in order to reduce the number of read system calls. All
assignment operations result in an immediate write-through of the corresponding
block. Note that in order to modify any portion of the disk, \fBfsdb\fR must be
invoked with the \fBw\fR option.
.sp
.LP
Wherever possible, \fBadb-\fRlike syntax was adopted to promote the use of
\fBfsdb\fR through familiarity.
.SH OPTIONS
.LP
The following option is supported:
.sp
.ne 2
.na
\fB\fB-o\fR\fR
.ad
.RS 6n
Specify \fBUFS\fR file system specific options. These options can be any
combination of the following separated by commas (with no intervening spaces).
The options available are:
.sp
.ne 2
.na
\fB\fB?\fR\fR
.ad
.RS 14n
Display usage
.RE

.sp
.ne 2
.na
\fB\fBo\fR\fR
.ad
.RS 14n
Override some error conditions
.RE

.sp
.ne 2
.na
\fB\fBp='string'\fR\fR
.ad
.RS 14n
set prompt to string
.RE

.sp
.ne 2
.na
\fB\fBw\fR\fR
.ad
.RS 14n
open for write
.RE

.RE

.SH USAGE
.LP
Numbers are considered hexadecimal by default. However, the user has control
over how data is to be displayed or accepted. The \fBbase\fR command will
display or set the input/output base. Once set, all input will default to this
base and all output will be shown in this base. The base can be overridden
temporarily for input by preceding hexadecimal numbers with \&'\fB0x\fR',
preceding decimal numbers with '\fB0t\fR', or octal numbers with '\fB0\fR'.
Hexadecimal numbers beginning with \fBa-f\fR or \fBA-F\fR must be preceded with
\&'\fB0x\fR' to distinguish them from commands.
.sp
.LP
Disk addressing by \fBfsdb\fR is at the byte level. However, \fBfsdb\fR offers
many commands to convert a desired inode, directory entry, block, superblock
and so forth to a byte address. Once the address has been calculated,
\fBfsdb\fR will record the result in dot (\fB\&.\fR).
.sp
.LP
Several global values are maintained by \fBfsdb\fR:
.RS +4
.TP
.ie t \(bu
.el o
the current base (referred to as \fBbase\fR),
.RE
.RS +4
.TP
.ie t \(bu
.el o
the current address (referred to as \fBdot\fR),
.RE
.RS +4
.TP
.ie t \(bu
.el o
the current inode (referred to as \fBinode\fR),
.RE
.RS +4
.TP
.ie t \(bu
.el o
the current count (referred to as \fBcount\fR),
.RE
.RS +4
.TP
.ie t \(bu
.el o
and the current type (referred to as \fBtype\fR).
.RE
.sp
.LP
Most commands use the preset value of \fBdot\fR in their execution. For
example,
.sp
.LP
\fB> 2:inode\fR
.sp
.LP
will first set the value of \fBdot\fR to 2, ':', will alert the start of a
command, and the \fBinode\fR command will set \fBinode\fR to 2. A count is
specified after a ','. Once set, \fBcount\fR will remain at this value until a
new command is encountered which will then reset the value back to 1 (the
default). So, if
.sp
.LP
\fB> 2000,400/X\fR
.sp
.LP
is typed, 400 hex longs are listed from 2000, and when completed, the value of
\fBdot\fR will be \fB2000 + 400 * sizeof (long)\fR. If a  \fBRETURN\fR is then
typed, the output routine will use the current values of \fBdot\fR,
\fBcount\fR, and \fBtype\fR and display 400 more hex longs. A '*' will cause
the entire block to be displayed.
.sp
.LP
End of fragment, block and file are maintained by \fBfsdb\fR. When displaying
data as fragments or blocks, an error message will be displayed when the end of
fragment or block is reached. When displaying data using the \fBdb\fR,
\fBib\fR, \fBdirectory\fR, or \fBfile\fR commands an error message is displayed
if the end of file is reached. This is mainly needed to avoid passing the end
of a directory or file and getting unknown and unwanted results.
.sp
.LP
An example showing several commands and the use of  \fBRETURN\fR would be:
.sp
.in +2
.nf
\fB> 2:ino; 0:dir?d\fR
      or
\fB> 2:ino; 0:db:block?d\fR
.fi
.in -2
.sp

.sp
.LP
The two examples are synonymous for getting to the first directory entry of the
root of the file system. Once there, any subsequent  \fBRETURN\fR (or +, -)
will advance to subsequent entries. Note that
.sp
.in +2
.nf
\fB> 2:inode; :ls\fR
      or
\fB> :ls /\fR
.fi
.in -2
.sp

.sp
.LP
is again synonymous.
.SS "Expressions"
.LP
The symbols recognized by \fBfsdb\fR are:
.sp
.ne 2
.na
\fB\fBRETURN\fR\fR
.ad
.RS 13n
update the value of \fBdot\fR by the current value of \fBtype\fR and display
using the current value of \fBcount\fR.
.RE

.sp
.ne 2
.na
\fB\fB#\fR\fR
.ad
.RS 13n
numeric expressions may be composed of +, -, *, and % operators (evaluated left
to right) and may use parentheses. Once evaluated, the value of \fBdot\fR is
updated.
.RE

.sp
.ne 2
.na
\fB\fB,\fR\fI count\fR\fR
.ad
.RS 13n
count indicator. The global value of \fBcount\fR will be updated to
\fBcount\fR. The value of \fBcount\fR will remain until a new command is run. A
count specifier of '*' will attempt to show a \fIblocks's\fR worth of
information. The default for \fBcount\fR is 1.
.RE

.sp
.ne 2
.na
\fB\fB?\fR\fI f\fR\fR
.ad
.RS 13n
display in structured style with format specifier \fIf\fR. See
\fBFormatted Output\fR.
.RE

.sp
.ne 2
.na
\fB\fB/\fR\fI f\fR\fR
.ad
.RS 13n
display in unstructured style with format specifier \fIf\fR. See
\fBFormatted Output\fR.
.RE

.sp
.ne 2
.na
\fB\fB\&.\fR\fR
.ad
.RS 13n
the value of \fBdot\fR.
.RE

.sp
.ne 2
.na
\fB\fB+\fR\fIe\fR\fR
.ad
.RS 13n
increment the value of \fBdot\fR by the expression \fIe.\fR The amount actually
incremented is dependent on the size of \fBtype\fR:
.sp
\fBdot = dot + e * sizeof (type)\fR
.sp
The default for \fIe\fR is \fB1\fR.
.RE

.sp
.ne 2
.na
\fB\fB-\fR\fIe\fR\fR
.ad
.RS 13n
decrement the value of \fBdot\fR by the expression \fIe\fR. See \fB+\fR.
.RE

.sp
.ne 2
.na
\fB\fB*\fR\fIe\fR\fR
.ad
.RS 13n
multiply the value of \fBdot\fR by the expression \fIe.\fR Multiplication and
division don't use \fBtype\fR. In the above calculation of \fBdot\fR, consider
the \fBsizeof(type)\fR to be \fB1\fR.
.RE

.sp
.ne 2
.na
\fB\fB%\fR\fIe\fR\fR
.ad
.RS 13n
divide the value of \fBdot\fR by the expression \fIe\fR. See \fB*\fR.
.RE

.sp
.ne 2
.na
\fB\fB<\fR\fI name\fR\fR
.ad
.RS 13n
restore an address saved in register \fIname\fR. \fIname\fR must be a single
letter or digit.
.RE

.sp
.ne 2
.na
\fB\fB>\fR\fI name\fR\fR
.ad
.RS 13n
save an address in register \fIname\fR. \fIname\fR must be a single letter or
digit.
.RE

.sp
.ne 2
.na
\fB\fB=\fR\fI f\fR\fR
.ad
.RS 13n
display indicator. If \fIf\fR is a legitimate format specifier, then the value
of \fBdot\fR is displayed using the format specifier \fIf\fR. See
\fBFormatted Output\fR. Otherwise, assignment is assumed. See \fB=\fR.
.RE

.sp
.ne 2
.na
\fB\fB= [\fR\fIs\fR\fB] [\fR\fIe\fR\fB]\fR\fR
.ad
.RS 13n
assignment indicator. The address pointed to by \fBdot\fR has its contents
changed to the value of the expression \fIe\fR or to the \fBASCII\fR
representation of the quoted (") string \fIs\fR. This may be useful for
changing directory names or \fBASCII\fR file information.
.RE

.sp
.ne 2
.na
\fB\fB=+\fR\fI e\fR\fR
.ad
.RS 13n
incremental assignment. The address pointed to by \fBdot\fR has its contents
incremented by expression \fIe\fR.
.RE

.sp
.ne 2
.na
\fB\fB=-\fR\fI e\fR\fR
.ad
.RS 13n
decremental assignment. The address pointed to by \fBdot\fR has its contents
decremented by expression \fIe\fR.
.RE

.SS "Commands"
.LP
A command must be prefixed by a ':' character. Only enough letters of the
command to uniquely distinguish it are needed. Multiple commands may be entered
on one line by separating them by a  \fBSPACE,\fR \fBTAB\fR or ';'.
.sp
.LP
In order to view a potentially unmounted disk in a reasonable manner,
\fBfsdb\fR offers the \fBcd\fR, \fBpwd\fR, \fBls\fR and \fBfind\fR commands.
The functionality of these commands substantially matches those of its UNIX
counterparts. See individual commands for details. The '*', '?', and '[-]' wild
card characters are available.
.sp
.ne 2
.na
\fB\fBbase=b\fR\fR
.ad
.sp .6
.RS 4n
display or set base. As stated above, all input and output is governed by the
current \fBbase\fR. If the  \fB=b\fR is omitted, the current \fBbase\fR is
displayed. Otherwise, the current \fBbase\fR is set to \fIb.\fR Note that this
is interpreted using the old value of \fBbase\fR, so to ensure correctness use
the '0', '0t', or '0x' prefix when changing the \fBbase\fR. The default for
\fBbase\fR is hexadecimal.
.RE

.sp
.ne 2
.na
\fB\fBblock\fR\fR
.ad
.sp .6
.RS 4n
convert the value of \fBdot\fR to a block address.
.RE

.sp
.ne 2
.na
\fB\fBcd \fR\fIdir\fR\fR
.ad
.sp .6
.RS 4n
change the current directory to directory \fIdir\fR. The current values of
\fBinode\fR and \fBdot\fR are also updated. If no \fIdir\fR is specified, then
change directories to inode \fB2\fR ("/").
.RE

.sp
.ne 2
.na
\fB\fBcg\fR\fR
.ad
.sp .6
.RS 4n
convert the value of \fBdot\fR to a cylinder group.
.RE

.sp
.ne 2
.na
\fB\fBdirectory\fR\fR
.ad
.sp .6
.RS 4n
If the current \fBinode\fR is a directory, then the value of \fBdot\fR is
converted to a directory slot offset in that directory and \fBdot\fR now points
to this entry.
.RE

.sp
.ne 2
.na
\fB\fBfile\fR\fR
.ad
.sp .6
.RS 4n
the value of \fBdot\fR is taken as a relative block count from the beginning of
the file. The value of \fBdot\fR is updated to the first byte of this block.
.RE

.sp
.ne 2
.na
\fB\fBfind\fR \fIdir\fR [ \fB-name\fR \fIn\fR] [\fB-inum\fR \fIi\fR]\fR
.ad
.sp .6
.RS 4n
find files by name or i-number. \fBfind\fR recursively searches directory
\fBdir\fR and below for filenames whose i-number matches \fIi\fR or whose name
matches pattern \fIn\fR. Note that only one of the two options (-name or -inum)
may be used at one time. Also, the -print is not needed or accepted.
.RE

.sp
.ne 2
.na
\fB\fBfill\fR\fI=p\fR\fR
.ad
.sp .6
.RS 4n
fill an area of disk with pattern \fIp\fR. The area of disk is delimited by
\fBdot\fR and \fBcount\fR.
.RE

.sp
.ne 2
.na
\fB\fBfragment\fR\fR
.ad
.sp .6
.RS 4n
convert the value of \fIdot\fR to a fragment address. The only difference
between the \fBfragment\fR command and the \fBblock\fR command is the amount
that is able to be displayed.
.RE

.sp
.ne 2
.na
\fB\fBinode\fR\fR
.ad
.sp .6
.RS 4n
convert the value of \fIdot\fR to an inode address. If successful, the current
value of \fBinode\fR will be updated as well as the value of \fIdot\fR. As a
convenient shorthand, if ':inode' appears at the beginning of the line, the
value of \fIdot\fR is set to the current \fBinode\fR and that inode is
displayed in inode format.
.RE

.sp
.ne 2
.na
\fB\fBlog_chk\fR\fR
.ad
.sp .6
.RS 4n
run through the valid log entries without printing any information and verify
the layout.
.RE

.sp
.ne 2
.na
\fB\fBlog_delta\fR\fR
.ad
.sp .6
.RS 4n
count the number of deltas into the log, using the value of dot as an offset
into the log. No checking is done to make sure that offset is within the
head/tail offsets.
.RE

.sp
.ne 2
.na
\fB\fBlog_head\fR\fR
.ad
.sp .6
.RS 4n
display the header information about the file system logging. This shows the
block allocation for the log and the data structures on the disk.
.RE

.sp
.ne 2
.na
\fB\fBlog_otodb\fR\fR
.ad
.sp .6
.RS 4n
return the physical disk block number, using the value of dot as an offset into
the log.
.RE

.sp
.ne 2
.na
\fB\fBlog_show\fR\fR
.ad
.sp .6
.RS 4n
display all deltas between  the beginning of the log (BOL) and the end of the
log (EOL).
.RE

.sp
.ne 2
.na
\fB\fBls\fR\fR
.ad
.sp .6
.RS 4n
[ \fB-R\fR ] [ \fB-l\fR ] \fIpat1 pat2\fR\|.\|.\|. list directories or files.
If no file is specified, the current directory is assumed. Either or both of
the options may be used (but, if used, \fImust\fR be specified before the
filename specifiers). Also, as stated above, wild card characters are available
and multiple arguments may be given. The long listing shows only the i-number
and the name; use the \fBinode\fR command with '?i' to get more information.
.RE

.sp
.ne 2
.na
\fB\fBoverride\fR\fR
.ad
.sp .6
.RS 4n
toggle the value of override. Some error conditions may be overridden if
override is toggled on.
.RE

.sp
.ne 2
.na
\fB\fBprompt\fR\fI p\fR\fR
.ad
.sp .6
.RS 4n
change the \fBfsdb\fR prompt to \fIp\fR. \fIp\fR must be surrounded by (")s.
.RE

.sp
.ne 2
.na
\fB\fBpwd\fR\fR
.ad
.sp .6
.RS 4n
display the current working directory.
.RE

.sp
.ne 2
.na
\fB\fBquit\fR\fR
.ad
.sp .6
.RS 4n
quit \fBfsdb\fR.
.RE

.sp
.ne 2
.na
\fB\fBsb\fR\fR
.ad
.sp .6
.RS 4n
the value of \fIdot\fR is taken as a cylinder group number and then converted
to the address of the superblock in that cylinder group. As a shorthand, ':sb'
at the beginning of a line will set the value of \fIdot\fR to \fIthe\fR
superblock and display it in superblock format.
.RE

.sp
.ne 2
.na
\fB\fBshadow\fR\fR
.ad
.sp .6
.RS 4n
if the current inode is a shadow inode, then the value of \fIdot\fR is set to
the beginning of the shadow inode data.
.RE

.sp
.ne 2
.na
\fB\fB!\fR\fR
.ad
.sp .6
.RS 4n
escape to shell
.RE

.SS "Inode Commands"
.LP
In addition to the above commands, there are several commands that deal with
inode fields and operate directly on the current \fBinode\fR (they still
require the ':'). They may be used to more easily display or change the
particular fields. The value of \fIdot\fR is only used by the '\fB:db\fR'
and '\fB:ib\fR' commands. Upon completion of the command, the value of \fIdot\fR is
changed to point to that particular field. For example,
.sp
.LP
\fB> :ln=+1\fR
.sp
.LP
would increment the link count of the current \fBinode\fR and set the value of
\fIdot\fR to the address of the link count field.
.sp
.ne 2
.na
\fB\fBat\fR\fR
.ad
.RS 7n
access time.
.RE

.sp
.ne 2
.na
\fB\fBbs\fR\fR
.ad
.RS 7n
block size.
.RE

.sp
.ne 2
.na
\fB\fBct\fR\fR
.ad
.RS 7n
creation time.
.RE

.sp
.ne 2
.na
\fB\fBdb\fR\fR
.ad
.RS 7n
use the current value of \fIdot\fR as a direct block index, where direct blocks
number from 0 - 11. In order to display the block itself, you need to 'pipe'
this result into the \fBblock\fR or \fBfragment\fR command. For example,
.sp
.in +2
.nf
\fB     > 1:db:block,20/X\fR
.fi
.in -2
.sp

would get the contents of data block field 1 from the inode and convert it to a
block address. 20 longs are then displayed in hexadecimal. See
\fBFormatted Output\fR.
.RE

.sp
.ne 2
.na
\fB\fBgid\fR\fR
.ad
.RS 7n
group id.
.RE

.sp
.ne 2
.na
\fB\fBib\fR\fR
.ad
.RS 7n
use the current value of \fIdot\fR as an indirect block index where indirect
blocks number from 0 - 2. This will only get the indirect block itself (the
block containing the pointers to the actual blocks). Use the \fBfile\fR command
and start at block 12 to get to the actual blocks.
.RE

.sp
.ne 2
.na
\fB\fBln\fR\fR
.ad
.RS 7n
link count.
.RE

.sp
.ne 2
.na
\fB\fBmt\fR\fR
.ad
.RS 7n
modification time.
.RE

.sp
.ne 2
.na
\fB\fBmd\fR\fR
.ad
.RS 7n
mode.
.RE

.sp
.ne 2
.na
\fB\fBmaj\fR\fR
.ad
.RS 7n
major device number.
.RE

.sp
.ne 2
.na
\fB\fBmin\fR\fR
.ad
.RS 7n
minor device number.
.RE

.sp
.ne 2
.na
\fB\fBnm\fR\fR
.ad
.RS 7n
although listed here, this command actually operates on the directory name
field. Once poised at the desired directory entry (using the \fIdirectory\fR
command), this command will allow you to change or display the directory name.
For example,
.sp
\fB> 7:dir:nm="foo"\fR
.sp
will get the \fB7\fRth directory entry of the current \fBinode\fR and change
its name to foo. Note that names cannot be made larger than the field is set up
for. If an attempt is made, the string is truncated to fit and a warning
message to this effect is displayed.
.RE

.sp
.ne 2
.na
\fB\fBsi\fR\fR
.ad
.RS 7n
shadow inode.
.RE

.sp
.ne 2
.na
\fB\fBsz\fR\fR
.ad
.RS 7n
file size.
.RE

.sp
.ne 2
.na
\fB\fBuid\fR\fR
.ad
.RS 7n
user id.
.RE

.SS "Formatted Output"
.LP
There are two styles and many format types. The two styles are structured and
unstructured. Structured output is used to display inodes, directories,
superblocks and the like. Unstructured displays raw data. The following shows
the different ways of displaying:
.sp
.ne 2
.na
\fB\fB?\fR\fR
.ad
.RS 5n
.sp
.ne 2
.na
\fB\fBc\fR\fR
.ad
.RS 5n
display as cylinder groups
.RE

.sp
.ne 2
.na
\fB\fBi\fR\fR
.ad
.RS 5n
display as inodes
.RE

.sp
.ne 2
.na
\fB\fBd\fR\fR
.ad
.RS 5n
display as directories
.RE

.sp
.ne 2
.na
\fB\fBs\fR\fR
.ad
.RS 5n
display as superblocks
.RE

.sp
.ne 2
.na
\fB\fBS\fR\fR
.ad
.RS 5n
display as shadow inode data
.RE

.RE

.sp
.ne 2
.na
\fB\fB/\fR\fR
.ad
.RS 5n
.sp
.ne 2
.na
\fB\fBb\fR\fR
.ad
.RS 7n
display as bytes
.RE

.sp
.ne 2
.na
\fB\fBc\fR\fR
.ad
.RS 7n
display as characters
.RE

.sp
.ne 2
.na
\fB\fBo O\fR\fR
.ad
.RS 7n
display as octal shorts or longs
.RE

.sp
.ne 2
.na
\fB\fBd D\fR\fR
.ad
.RS 7n
display as decimal shorts or longs
.RE

.sp
.ne 2
.na
\fB\fBx X\fR\fR
.ad
.RS 7n
display as hexadecimal shorts or longs
.RE

The format specifier immediately follows the '/' or '?' character. The values
displayed by '/b' and all '?' formats are displayed in the current \fBbase\fR.
Also, \fBtype\fR is appropriately updated upon completion.
.RE

.SH EXAMPLES
.LP
\fBExample 1 \fRDisplaying in Decimal
.sp
.LP
The following command displays \fB2010\fR in decimal (use of \fBfsdb\fR as a
calculator for complex arithmetic):

.sp
.in +2
.nf
> 2000+400%(20+20)=D
.fi
.in -2
.sp

.LP
\fBExample 2 \fRDisplaying an i-number in Inode Format
.sp
.LP
The following command displays i-number \fB386\fR in an inode format. This now
becomes the current \fBinode\fR:

.sp
.in +2
.nf
> 386:ino?i
.fi
.in -2
.sp

.LP
\fBExample 3 \fRChanging the Link Count
.sp
.LP
The following command changes the link count for the current \fBinode\fR to
\fB4\fR:

.sp
.in +2
.nf
> :ln=4
.fi
.in -2
.sp

.LP
\fBExample 4 \fRIncrementing the Link Count
.sp
.LP
The following command increments the link count by \fB1\fR:

.sp
.in +2
.nf
> :ln=+1
.fi
.in -2
.sp

.LP
\fBExample 5 \fRDisplaying the Creation Time
.sp
.LP
The following command displays the creation time as a hexadecimal long:

.sp
.in +2
.nf
> :ct=X
.fi
.in -2
.sp

.LP
\fBExample 6 \fRDisplaying the Modification Time
.sp
.LP
The following command displays the modification time in time format:

.sp
.in +2
.nf
> :mt=t
.fi
.in -2
.sp

.LP
\fBExample 7 \fRDisplaying in ASCII
.sp
.LP
The following command displays in \fBASCII,\fR block zero of the file
associated with the current \fBinode\fR:

.sp
.in +2
.nf
> 0:file/c
.fi
.in -2
.sp

.LP
\fBExample 8 \fRDisplaying the First Block's Worth of Directorty Entries
.sp
.LP
The following command displays the first block's worth of directory entries for
the root inode of this file system. It will stop prematurely if the \fBEOF\fR
is reached:

.sp
.in +2
.nf
> 2:ino,*?d
.fi
.in -2
.sp

.LP
\fBExample 9 \fRDisplaying Changes to the Current Inode
.sp
.LP
The following command displays changes the current inode to that associated
with the \fB5\fRth directory entry (numbered from zero) of the current
\fBinode\fR. The first logical block of the file is then displayed in
\fBASCII\fR:

.sp
.in +2
.nf
> 5:dir:inode; 0:file,*/c
.fi
.in -2
.sp

.LP
\fBExample 10 \fRDisplaying the Superblock
.sp
.LP
The following command displays the superblock of this file system:

.sp
.in +2
.nf
> :sb
.fi
.in -2
.sp

.LP
\fBExample 11 \fRDisplaying the Cylinder Group
.sp
.LP
The following command displays cylinder group information and summary for
cylinder group \fB1\fR:

.sp
.in +2
.nf
> 1:cg?c
.fi
.in -2
.sp

.LP
\fBExample 12 \fRChanging the i-number
.sp
.LP
The following command changes the i-number for the seventh directory slot in
the root directory to \fB3\fR:

.sp
.in +2
.nf
> 2:inode; 7:dir=3
.fi
.in -2
.sp

.LP
\fBExample 13 \fRDisplaying as Directory Entries
.sp
.LP
The following command displays the third block of the current \fBinode\fR as
directory entries:

.sp
.in +2
.nf
> 2:db:block,*?d
.fi
.in -2
.sp

.LP
\fBExample 14 \fRChanging the Name Field
.sp
.LP
The following command changes the name field in the directory slot to
\fIname\fR:

.sp
.in +2
.nf
> 7:dir:nm="name"
.fi
.in -2
.sp

.LP
\fBExample 15 \fRGetting and Filling Elements
.sp
.LP
The following command gets fragment \fB3c3\fR and fill \fB20\fR \fBtype\fR
elements with \fB0x20\fR:

.sp
.in +2
.nf
> 3c3:fragment,20:fill=0x20
.fi
.in -2
.sp

.LP
\fBExample 16 \fRSetting the Contents of an Address
.sp
.LP
The following command sets the contents of address \fB2050\fR to
\fB0xffffffff\fR. \fB0xffffffff\fR may be truncated depending on the current
\fBtype\fR:

.sp
.in +2
.nf
> 2050=0xffff
.fi
.in -2
.sp

.LP
\fBExample 17 \fRPlacing ASCII
.sp
.LP
The following command places the \fBASCII\fR for the string at \fB1c92434\fR:

.sp
.in +2
.nf
> 1c92434="this is some text"
.fi
.in -2
.sp

.LP
\fBExample 18 \fRDisplaying Shadow Inode Data
.sp
.LP
The following command displays all of the shadow inode data in the shadow inode
associated with the root inode of this file system:

.sp
.in +2
.nf
> 2:ino:si:ino;0:shadow,*?S
.fi
.in -2
.sp

.SH SEE ALSO
.LP
\fBclri\fR(1M), \fBfsck_ufs\fR(1M), \fBdir_ufs\fR(4), \fBattributes\fR(5),
\fBufs\fR(7FS)
.SH WARNINGS
.LP
Since \fBfsdb\fR reads the disk raw, extreme caution is advised in determining
its availability of \fBfsdb\fR on the system. Suggested permissions are 600 and
owned by bin.
.SH NOTES
.LP
The old command line syntax for clearing i-nodes using the ufs-specific
\fB\&'-z i-number'\fR option is still supported by the new debugger, though it
is obsolete and will be removed in a future release. Use of this flag will
result in correct operation, but an error message will be printed warning of
the impending obsolesence of this option to the command. The equivalent
functionality is available using the more flexible \fBclri\fR(1M) command.