Tribblix: manual page: od.1

OD(1) User Commands OD(1)

NAME

od - octal dump

SYNOPSIS

/usr/bin/od [-bcCDdFfOoSsvXx] [-] [file] [offset_string]

/usr/bin/od [-bcCDdFfOoSsvXx] [-A address_base] [-j skip]
[-N count] [-t type_string]... [-] [file]...

/usr/xpg4/bin/od [-bcCDdFfOoSsvXx] [file] [offset_string]

/usr/xpg4/bin/od [-bcCDdFfOoSsvXx] [-A address_base]
[-j skip] [-N count] [-t type_string]... [file]...

DESCRIPTION

The od command copies sequentially each input file to standard output
and transforms the input data according to the output types specified
by the -t or -bcCDdFfOoSsvXx options. If no output type is specified,
the default output is as if -t o2 had been specified. Multiple types
can be specified by using multiple -bcCDdFfOoSstvXx options. Output
lines are written for each type specified in the order in which the
types are specified. If no file is specified, the standard input is
used. The [offset_string] operand is mutually exclusive from the -A,
-j, -N, and -t options. For the purposes of this description, the
following terms are used:

word
Refers to a 16-bit unit, independent of the word
size of the machine.

long word
Refers to a 32-bit unit.

double long word
Refers to a 64-bit unit.

OPTIONS

The following options are supported:

-A address_base
Specifies the input offset base. The address_base
option-argument must be a character. The
characters d, o and x specify that the offset
base will be written in decimal, octal or
hexadecimal, respectively. The character n
specifies that the offset will not be written.
Unless -A n is specified, the output line will be
preceded by the input offset, cumulative across
input files, of the next byte to be written. In
addition, the offset of the byte following the
last byte written will be displayed after all the
input data has been processed. Without the -A
address_base option and the [offset_string]
operand, the input offset base is displayed in
octal.

-b
Interprets bytes in octal. This is equivalent to
-t o1.

/usr/bin/od
-c
Displays single-byte characters. Certain non-graphic
characters appear as C-language escapes:

null \0
backspace \b
form-feed \f
new-line \n
return \r
tab \t

Others appear as 3-digit octal numbers. For example:

echo "hello world" | od -c
0000000 h e l l o w o r l d \n
0000014

/usr/xpg4/bin/od
-c
Interprets bytes as single-byte or multibyte
characters according to the current setting of the
LC_CTYPE locale category. Printable multibyte
characters are written in the area corresponding
to the first byte of the character. The two-
character sequence ** is written in the area
corresponding to each remaining byte in the
character, as an indication that the character is
continued. Non-graphic characters appear the same
as they would using the -C option.

-C
Interprets bytes as single-byte or multibyte
characters according to the current setting of the
LC_CTYPE locale category. Printable multibyte
characters are written in the area corresponding
to the first byte of the character. The two-
character sequence ** is written in the area
corresponding to each remaining byte in the
character, as an indication that the character is
continued. Certain non-graphic characters appear
as C escapes:

null \0
backspace \b
form-feed \f
new-line \n
return \r
tab \t

Other non-printable characters appear as one
three-digit octal number for each byte in the
character.

-d
Interprets words in unsigned decimal. This is
equivalent to -t u2.

-D
Interprets long words in unsigned decimal. This is
equivalent to -t u4.

-f
Interprets long words in floating point. This is
equivalent to -t f4.

-F
Interprets double long words in extended
precision. This is equivalent to -t f8.

-j skip
Jumps over skip bytes from the beginning of the
input. The od command will read or seek past the
first skip bytes in the concatenated input files.
If the combined input is not at least skip bytes
long, the od command will write a diagnostic
message to standard error and exit with a non-zero
exit status.

By default, the skip option-argument is
interpreted as a decimal number. With a leading
0x or 0X, the offset is interpreted as a
hexadecimal number; otherwise, with a leading 0,
the offset will be interpreted as an octal number.
Appending the character b, k, or m to offset will
cause it to be interpreted as a multiple of 512,
1024 or 1048576 bytes, respectively. If the skip
number is hexadecimal, any appended b is
considered to be the final hexadecimal digit. The
address is displayed starting at 0000000, and its
base is not implied by the base of the skip
option-argument.

-N count
Formats no more than count bytes of input. By
default, count is interpreted as a decimal number.
With a leading 0x or 0X, count is interpreted as a
hexadecimal number; otherwise, with a leading 0,
it is interpreted as an octal number. If count
bytes of input (after successfully skipping, if
-jskip is specified) are not available, it will
not be considered an error. The od command will
format the input that is available. The base of
the address displayed is not implied by the base
of the count option-argument.

-o
Interprets words in octal. This is equivalent to
-t o2.

-O
Interprets long words in unsigned octal. This is
equivalent to -t o4.

-s
Interprets words in signed decimal. This is
equivalent to -t d2.

-S
Interprets long words in signed decimal. This is
equivalent to -t d4.

-t type_string
Specifies one or more output types. The
type_string option-argument must be a string
specifying the types to be used when writing the
input data. The string must consist of the type
specification characters:

a
Named character. Interprets bytes as named
characters. Only the least significant seven
bits of each byte will be used for this type
specification. Bytes with the values listed
in the following table will be written using
the corresponding names for those
characters.

The following are named characters in od:

Value Name

\000 nul
\001 soh
\002 stx
\003 etx
\004 eot
\005 enq
\006 ack
\007 bel
\010 bs
\011 ht
\012 lf
\013 vt
\014 ff
\015 cr
\016 so
\017 si
\020 dle
\021 dc1
\022 dc2
\023 dc3
\024 dc4
\025 nak
\026 syn
\027 etb
\030 can
\031 em
\032 sub
\033 esc
\034 fs
\035 gs
\036 rs
\037 us
\040 sp
\177 del

c
Character. Interprets bytes as single-byte
or multibyte characters specified by the
current setting of the LC_CTYPE locale
category. Printable multibyte characters
are written in the area corresponding to the
first byte of the character. The two-
character sequence ** is written in the area
corresponding to each remaining byte in the
character, as an indication that the
character is continued. Certain non-graphic
characters appear as C escapes: \0, \a, \b,
\f, \n, \r, \t, \v. Other non-printable
characters appear as one three-digit octal
number for each byte in the character.

The type specification characters d, f, o, u, and
x can be followed by an optional unsigned decimal
integer that specifies the number of bytes to be
transformed by each instance of the output type.

f
Floating point. Can be followed
by an optional F, D, or L
indicating that the conversion
should be applied to an item of
type float, double, or long
double, respectively.

d, o, u, and x
Signed decimal, octal, unsigned
decimal, and hexadecimal,
respectively. Can be followed by
an optional C, S, I, or L
indicating that the conversion
should be applied to an item of
type char, short, int, or long,
respectively.

Multiple types can be concatenated within the same
type_string and multiple -t options can be
specified. Output lines are written for each type
specified in the order in which the type
specification characters are specified.

-v
Shows all input data (verbose). Without the -v
option, all groups of output lines that would be
identical to the immediately preceding output line
(except for byte offsets), will be replaced with a
line containing only an asterisk (*).

-x
Interprets words in hex. This is equivalent to -t
x2.

-X
Interprets long words in hex. This is equivalent
to -t x4.

OPERANDS

/usr/bin/od
The following operands are supported for /usr/bin/od only:

-
Uses the standard input in addition to any
files specified. When this operand is not
given, the standard input is used only if
no file operands are specified.

file
A path name of a file to be read. If no
file operands are specified, the standard
input will be used. If there are no more
than two operands, none of the -A, -j, -N,
or -t options is specified, and any of the
following are true:

1. the first character of the last
operand is a plus sign (+)

2. the first character of the
second operand is numeric

3. the first character of the
second operand is x and the
second character of the second
operand is a lower-case
hexadecimal character or digit

4. the second operand is named "x"

5. the second operand is named "."
then the corresponding operand is assumed
to be an offset operand rather than a file
operand.

Without the -N count option, the display
continues until an end-of-file is reached.

[+][0] offset [.][b|B]
[+][0][offset] [.]
[+][0x|x][offset]
[+][0x|x] offset[B]
The offset_string operand specifies the
byte offset in the file where dumping is to
commence. The offset is interpreted in
octal bytes by default. If offset begins
with "0", it is interpreted in octal. If
offset begins with "x" or "0x", it is
interpreted in hexadecimal and any appended
"b" is considered to be the final
hexadecimal digit. If "." is appended, the
offset is interpreted in decimal. If "b" or
"B" is appended, the offset is interpreted
in units of 512 bytes. If the file argument
is omitted, the offset argument must be
preceded by a plus sign (+). The address
is displayed starting at the given offset.
The radix of the address will be the same
as the radix of the offset, if specified,
otherwise it will be octal. Decimal
overrides octal, and it is an error to
specify both hexadecimal and decimal
conversions in the same offset operand.

/usr/xpg4/bin/od
The following operands are supported for /usr/xpg4/bin/od only:

file
Same as /usr/bin/od, except only one of
the first two conditions must be true.

[+] [0] offset [.][b|B]
+ [offset] [.]
[+][0x][offset]
[+][0x] offset[B]
+x [offset]
+xoffset [B]
Description of offset_string is the same
as for /usr/bin/od.

ENVIRONMENT VARIABLES

See environ(7) for descriptions of the following environment
variables that affect the execution of od: LANG, LC_ALL, LC_CTYPE,
LC_MESSAGES, LC_NUMERIC, and NLSPATH.

EXIT STATUS

The following exit values are returned:

0
Successful completion.

>0
An error occurred.

ATTRIBUTES