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.\"	@(#)od.1	8.1 (Berkeley) 6/6/93
.\" $FreeBSD$
.\"
.Dd December 22, 2011
.Dt OD 1
.Os
.Sh NAME
.Nm od
.Nd octal, decimal, hex, ASCII dump
.Sh SYNOPSIS
.Nm
.Op Fl aBbcDdeFfHhIiLlOosvXx
.Op Fl A Ar base
.Op Fl j Ar skip
.Op Fl N Ar length
.Op Fl t Ar type
.Op Oo Cm + Oc Ns Ar offset Ns Oo Cm \&. Oc Ns Op Cm Bb
.Op Ar
.Sh DESCRIPTION
The
.Nm
utility is a filter which displays the specified files, or standard
input if no files are specified, in a user specified format.
.Pp
The options are as follows:
.Bl -tag -width ".Fl I , L , l"
.It Fl A Ar base
Specify the input address base.
The argument
.Ar base
may be one of
.Cm d ,
.Cm o ,
.Cm x
or
.Cm n ,
which specify decimal, octal, hexadecimal
addresses or no address, respectively.
.It Fl a
Output named characters.
Equivalent to
.Fl t Cm a .
.It Fl B , o
Output octal shorts.
Equivalent to
.Fl t Cm o2 .
.It Fl b
Output octal bytes.
Equivalent to
.Fl t Cm o1 .
.It Fl c
Output C-style escaped characters.
Equivalent to
.Fl t Cm c .
.It Fl D
Output unsigned decimal ints.
Equivalent to
.Fl t Cm u4 .
.It Fl d
Output unsigned decimal shorts.
Equivalent to
.Fl t Cm u2 .
.It Fl e , F
Output double-precision floating point numbers.
Equivalent to
.Fl t Cm fD .
.It Fl f
Output single-precision floating point numbers.
Equivalent to
.Fl t Cm fF .
.It Fl H , X
Output hexadecimal ints.
Equivalent to
.Fl t Cm x4 .
.It Fl h , x
Output hexadecimal shorts.
Equivalent to
.Fl t Cm x2 .
.It Fl I , L , l
Output signed decimal longs.
Equivalent to
.Fl t Cm dL .
.It Fl i
Output signed decimal ints.
Equivalent to
.Fl t Cm dI .
.It Fl j Ar skip
Skip
.Ar skip
bytes of the combined input before dumping.
The number may be followed by one
of
.Cm b , k
or
.Cm m
which specify the units of the number as blocks (512 bytes), kilobytes and
megabytes, respectively.
.It Fl N Ar length
Dump at most
.Ar length
bytes of input.
.It Fl O
Output octal ints.
Equivalent to
.Fl t Cm o4 .
.It Fl s
Output signed decimal shorts.
Equivalent to
.Fl t Cm d2 .
.It Fl t Ar type
Specify the output format.
The
.Ar type
argument
is a string containing one or more of the following kinds of type specifiers:
.Bl -tag -width indent
.It Cm a
Named characters
.Pq Tn ASCII .
Control characters are displayed using the following names:
.Bl -column "000 NUL" "001 SOH" "002 STX" "003 ETX" "004 EOT" "005 ENQ"
.It "000 NUL	001 SOH	002 STX	003 ETX	004 EOT	005 ENQ"
.It "006 ACK	007 BEL	008 BS	009 HT	00A NL	00B VT"
.It "00C FF	00D CR	00E SO	00F SI	010 DLE	011 DC1"
.It "012 DC2	013 DC3	014 DC4	015 NAK	016 SYN	017 ETB"
.It "018 CAN	019 EM	01A SUB	01B ESC	01C FS	01D GS"
.It "01E RS	01F US	020 SP	07F DEL	\&	\&"
.El
.It Cm c
Characters in the default character set.
Non-printing characters are
represented as 3-digit octal character codes, except the following
characters, which are represented as C escapes:
.Pp
.Bl -tag -width carriage-return -compact
.It NUL
\e0
.It alert
\ea
.It backspace
\eb
.It newline
\en
.It carriage-return
\er
.It tab
\et
.It vertical tab
\ev
.El
.Pp
Multi-byte characters are displayed in the area corresponding to the first
byte of the character.
The remaining bytes are shown as
.Ql ** .
.It Xo
.Sm off
.Op Cm d | o | u | x
.Op Cm C | S | I | L | Ar n
.Sm on
.Xc
Signed decimal
.Pq Cm d ,
octal
.Pq Cm o ,
unsigned decimal
.Pq Cm u
or
hexadecimal
.Pq Cm x .
Followed by an optional size specifier, which may be either
.Cm C
.Pq Vt char ,
.Cm S
.Pq Vt short ,
.Cm I
.Pq Vt int ,
.Cm L
.Pq Vt long ,
or a byte count as a decimal integer.
.It Xo
.Sm off
.Cm f
.Op Cm F | D | L | Ar n
.Sm on
.Xc
Floating-point number.
Followed by an optional size specifier, which may be either
.Cm F
.Pq Vt float ,
.Cm D
.Pq Vt double
or
.Cm L
.Pq Vt "long double" .
.El
.It Fl v
Write all input data, instead of replacing lines of duplicate values with a
.Ql * .
.El
.Pp
Multiple options that specify output format may be used; the output will
contain one line for each format.
.Pp
If no output format is specified,
.Fl t Cm oS
is assumed.
.Sh ENVIRONMENT
The
.Ev LANG , LC_ALL
and
.Ev LC_CTYPE
environment variables affect the execution of
.Nm
as described in
.Xr environ 7 .
.Sh EXIT STATUS
.Ex -std
.Sh COMPATIBILITY
The traditional
.Fl s
option to extract string constants is not supported; consider using
.Xr strings 1
instead.
.Sh SEE ALSO
.Xr hexdump 1 ,
.Xr strings 1
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.1-2001 .
.Sh HISTORY
An
.Nm
command appeared in
.At v1 .