od is a command that dumps binary files to eight digits.
od [-aBbcDdeFfHhIiLlOosvXx] [-A base] [-j skip] [-N length] [-t type] [[+]offset[.][Bb]] [file ...]| Option | Description |
|---|---|
| -A base | Specify the input address base. The argument base may be one of d, o, x or n, which specify decimal, octal, hexadecimal addresses or no address, respectively. |
| -a | Output named characters. Equivalent to -t a. |
| -B, -o | Output octal shorts. Equivalent to -t o2. |
| -b | Output octal bytes. Equivalent to -t o1. |
| -c | Output C-style escaped characters. Equivalent to -t c. |
| -D | Output unsigned decimal ints. Equivalent to -t u4. |
| -d | Output unsigned decimal shorts. Equivalent to -t u2. |
| -e, -F | Output double-precision floating point numbers. Equivalent to -t fD. |
| -f | Output single-precision floating point numbers. Equivalent to -t fF. |
| -H, -X | Output hexadecimal ints. Equivalent to -t x4. |
| -h, -x | Output hexadecimal shorts. Equivalent to -t x2. |
| -I, -L, -l | Output signed decimal longs. Equivalent to -t dL. |
| -i | Output signed decimal ints. Equivalent to -t dI. |
| -j skip | Skip skip bytes of the combined input before dumping. The number may be followed by one of b, k, m or g which specify the units of the number as blocks (512 bytes), kilobytes, megabytes and gigabytes, respectively. |
| -N length | Dump at most length bytes of input. |
| -O | Output octal ints. Equivalent to -t o4. |
| -s | Output signed decimal shorts. Equivalent to -t d2. |
| -t type | Specify the output format. The type argument is a string containing one or more of the following kinds of type specifiers. |
| a | Named characters (ASCII). Control characters are displayed using the following names: |
| 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 like \0, \n, \t, so on. Multi-byte characters are displayed in the area corresponding to the first byte of the character. The remaining bytes are shown as ‘**’. |
| [d | o |
| f[F | D |
| -v | Write all input data, instead of replacing lines of duplicate values with a ‘*’. |
Example
File test’s content is:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890od -t x1 test -> Express the test file by 1 byte in hexadecimal.
$ od -t x1 test0000000 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 700000020 71 72 73 74 75 76 77 78 79 7a 41 42 43 44 45 460000040 47 48 49 4a 4b 4c 4d 4e 4f 50 51 52 53 54 55 560000060 57 58 59 5a 31 32 33 34 35 36 37 38 39 30 0a0000077od -t x1z test -> Express 1 byte by hexadecimal and display ASCII characters on the below.
$ od -t x1c test0000000 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 70 a b c d e f g h i j k l m n o p0000020 71 72 73 74 75 76 77 78 79 7a 41 42 43 44 45 46 q r s t u v w x y z A B C D E F0000040 47 48 49 4a 4b 4c 4d 4e 4f 50 51 52 53 54 55 56 G H I J K L M N O P Q R S T U V0000060 57 58 59 5a 31 32 33 34 35 36 37 38 39 30 0a W X Y Z 1 2 3 4 5 6 7 8 9 0 \n0000077od -Ad test -> Print as demical.
$ od -Ad test0000000 061141 062143 063145 064147 065151 066153 067155 0701570000016 071161 072163 073165 074167 075171 041101 042103 0431050000032 044107 045111 046113 047115 050117 051121 052123 0531250000048 054127 055131 031061 032063 033065 034067 030071 0000120000063reference
