od — dump files in octal and other formats
Examples (TL;DR)
-
Display file using default settings: octal format, 8 bytes per line, byte offsets in octal, and duplicate lines replaced with
*:od path/to/file -
Display file in verbose mode, i.e. without replacing duplicate lines with
*:od -v path/to/file -
Display file in hexadecimal format (2-byte units), with byte offsets in decimal format:
od --format=x --address-radix=d -v path/to/file -
Display file in hexadecimal format (1-byte units), and 4 bytes per line:
od --format=x1 --width=4 -v path/to/file -
Display file in hexadecimal format along with its character representation, and do not print byte offsets:
od --format=xz --address-radix=n -v path/to/file -
Read only 100 bytes of a file starting from the 500th byte:
od --read-bytes 100 --skip-bytes=500 -v path/to/file
Synopsis
od [OPTION]... [FILE]...
od [-abcdfilosx]... [FILE] [[+]OFFSET[.][b]]
od --traditional [OPTION]... [FILE] [[+]OFFSET[.][b] [+][LABEL][.][b]]
Description
Write an unambiguous representation, octal bytes by default, of FILE to standard output. With more than one FILE argument, concatenate them in the listed order to form the input.
With no FILE, or when FILE is -, read standard input.
If first and second call formats both apply, the second format is assumed if the last operand begins with + or (if there are 2 operands) a digit. An OFFSET operand means -j OFFSET. LABEL is the pseudo-address at first byte printed, incremented when dump is progressing. For OFFSET and LABEL, a 0x or 0X prefix indicates hexadecimal; suffixes may be . for octal and b for multiply by 512.
Mandatory arguments to long options are mandatory for short options too.
- -A, --address-radix=RADIX
output format for file offsets; RADIX is one of [doxn], for Decimal, Octal, Hex or None
- --endian={big|little}
swap input bytes according the specified order
- -j, --skip-bytes=BYTES
skip BYTES input bytes first
- -N, --read-bytes=BYTES
limit dump to BYTES input bytes
- -S BYTES, --strings[=BYTES]
output strings of at least BYTES graphic chars; 3 is implied when BYTES is not specified
- -t, --format=TYPE
select output format or formats
- -v, --output-duplicates
do not use * to mark line suppression
- -w[BYTES], --width[=BYTES]
output BYTES bytes per output line; 32 is implied when BYTES is not specified
- --traditional
accept arguments in third form above
- --help
display this help and exit
- --version
output version information and exit
Traditional format specifications may be intermixed; they accumulate
- -a
same as -t a, select named characters, ignoring high-order bit
- -b
same as -t o1, select octal bytes
- -c
same as -t c, select printable characters or backslash escapes
- -d
same as -t u2, select unsigned decimal 2-byte units
- -f
same as -t fF, select floats
- -i
same as -t dI, select decimal ints
- -l
same as -t dL, select decimal longs
- -o
same as -t o2, select octal 2-byte units
- -s
same as -t d2, select decimal 2-byte units
- -x
same as -t x2, select hexadecimal 2-byte units
TYPE is made up of one or more of these specifications
- a
named character, ignoring high-order bit
- c
printable character or backslash escape
- d[SIZE]
signed decimal, SIZE bytes per integer
- f[SIZE]
floating point, SIZE bytes per float
- o[SIZE]
octal, SIZE bytes per integer
- u[SIZE]
unsigned decimal, SIZE bytes per integer
- x[SIZE]
hexadecimal, SIZE bytes per integer
SIZE is a number. For TYPE in [doux], SIZE may also be C for sizeof(char), S for sizeof(short), I for sizeof(int) or L for sizeof(long). If TYPE is f, SIZE may also be F for sizeof(float), D for sizeof(double) or L for sizeof(long double).
Adding a z suffix to any type displays printable characters at the end of each output line.
BYTES is hex with 0x or 0X prefix, and may have a multiplier suffix
- b
512
- KB
1000
- K
1024
- MB
1000*1000
- M
1024*1024
and so on for G, T, P, E, Z, Y. Binary prefixes can be used, too: KiB=K, MiB=M, and so on.
Examples
- od -A x -t x1z -v
Display hexdump format output
- od -A o -t oS -w16
The default output format used by od
Reporting Bugs
GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>
Copyright
Copyright © 2019 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
See Also
Full documentation <https://www.gnu.org/software/coreutils/od>
or available locally via: info '(coreutils) od invocation'
Referenced By
editcap(1), file(1), hexedit(1), scr_dump(5), spew(1), tcpbug(1), text2pcap(1).