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od(1) [osx man page]

OD(1)							    BSD General Commands Manual 						     OD(1)

NAME
od -- octal, decimal, hex, ASCII dump SYNOPSIS
od [-aBbcDdeFfHhIiLlOosvXx] [-A base] [-j skip] [-N length] [-t type] [[+]offset[.][Bb]] [file ...] DESCRIPTION
The od utility is a filter which displays the specified files, or standard input if no files are specified, in a user specified format. The options are as follows: -A base Specify the input address base. 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. -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 or m which specify the units of the number as blocks (512 bytes), kilobytes and megabytes, 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. type 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: 000 NUL 001 SOH 002 STX 003 ETX 004 EOT 005 ENQ 006 ACK 007 BEL 008 BS 009 HT 00a NL 00b VT 00c FF 00d CR 00e SO 00f SI 010 DLE 011 DC1 012 DC2 013 DC3 014 DC4 015 NAK 016 SYN 017 ETB 018 CAN 019 EM 01a SUB 01b ESC 01c FS 01d GS 01e RS 01f US 020 SP 0ff DEL 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: NUL alert a backspace  newline carriage-return tab vertical tab v Multi-byte characters are displayed in the area corresponding to the first byte of the character. The remaining bytes are shown as '**'. [d|o|u|x][C|S|I|L|n] Signed decimal (d), octal (o), unsigned decimal (u) or hexadecimal (x). Followed by an optional size specifier, which may be either C (char), S (short), I (int), L (long), or a byte count as a decimal integer. f[F|D|L|n] Floating-point number. Followed by an optional size specifier, which may be either F (float), D (double) or L (long double). -v Write all input data, instead of replacing lines of duplicate values with a '*'. Multiple options that specify output format may be used; the output will contain one line for each format. If no output format is specified, -t oS is assumed. ENVIRONMENT
The LANG, LC_ALL and LC_CTYPE environment variables affect the execution of od as described in environ(7). DIAGNOSTICS
The od utility exits 0 on success, and >0 if an error occurs. COMPATIBILITY
The traditional -s option to extract string constants is not supported; consider using strings(1) instead. SEE ALSO
hexdump(1), strings(1) STANDARDS
The od utility conforms to IEEE Std 1003.1-2001 (``POSIX.1''). HISTORY
An od command appeared in Version 1 AT&T UNIX. BSD
July 11, 2004 BSD

Check Out this Related Man Page

HEXDUMP(1)						    BSD General Commands Manual 						HEXDUMP(1)

NAME
hexdump, hd -- ASCII, decimal, hexadecimal, octal dump SYNOPSIS
hexdump [-bcCdovx] [-e format_string] [-f format_file] [-n length] [-s skip] file ... hd [-bcdovx] [-e format_string] [-f format_file] [-n length] [-s skip] file ... DESCRIPTION
The hexdump utility is a filter which displays the specified files, or the standard input, if no files are specified, in a user specified format. The options are as follows: -b One-byte octal display. Display the input offset in hexadecimal, followed by sixteen space-separated, three column, zero-filled, bytes of input data, in octal, per line. -c One-byte character display. Display the input offset in hexadecimal, followed by sixteen space-separated, three column, space- filled, characters of input data per line. -C Canonical hex+ASCII display. Display the input offset in hexadecimal, followed by sixteen space-separated, two column, hexadecimal bytes, followed by the same sixteen bytes in %_p format enclosed in ``|'' characters. Calling the command hd implies this option. -d Two-byte decimal display. Display the input offset in hexadecimal, followed by eight space-separated, five column, zero-filled, two- byte units of input data, in unsigned decimal, per line. -e format_string Specify a format string to be used for displaying data. -f format_file Specify a file that contains one or more newline separated format strings. Empty lines and lines whose first non-blank character is a hash mark (#) are ignored. -n length Interpret only length bytes of input. -o Two-byte octal display. Display the input offset in hexadecimal, followed by eight space-separated, six column, zero-filled, two byte quantities of input data, in octal, per line. -s offset Skip offset bytes from the beginning of the input. By default, offset is interpreted as a decimal number. With a leading 0x or 0X, offset is interpreted as a hexadecimal number, otherwise, with a leading 0, offset is interpreted as an octal number. Appending the character b, k, or m to offset causes it to be interpreted as a multiple of 512, 1024, or 1048576, respectively. -v Cause hexdump to display all input data. Without the -v option, any number of groups of output lines, which would be identical to the immediately preceding group of output lines (except for the input offsets), are replaced with a line comprised of a single aster- isk. -x Two-byte hexadecimal display. Display the input offset in hexadecimal, followed by eight, space separated, four column, zero-filled, two-byte quantities of input data, in hexadecimal, per line. For each input file, hexdump sequentially copies the input to standard output, transforming the data according to the format strings speci- fied by the -e and -f options, in the order that they were specified. Formats A format string contains any number of format units, separated by whitespace. A format unit contains up to three items: an iteration count, a byte count, and a format. The iteration count is an optional positive integer, which defaults to one. Each format is applied iteration count times. The byte count is an optional positive integer. If specified it defines the number of bytes to be interpreted by each iteration of the for- mat. If an iteration count and/or a byte count is specified, a single slash must be placed after the iteration count and/or before the byte count to disambiguate them. Any whitespace before or after the slash is ignored. The format is required and must be surrounded by double quote (" ") marks. It is interpreted as a fprintf-style format string (see fprintf(3)), with the following exceptions: o An asterisk (*) may not be used as a field width or precision. o A byte count or field precision is required for each ``s'' conversion character (unlike the fprintf(3) default which prints the entire string if the precision is unspecified). o The conversion characters ``%'', ``h'', ``l'', ``n'', ``p'' and ``q'' are not supported. o The single character escape sequences described in the C standard are supported: NUL <alert character> a <backspace>  <form-feed> f <newline> <carriage return> <tab> <vertical tab> v The hexdump utility also supports the following additional conversion strings: _a[dox] Display the input offset, cumulative across input files, of the next byte to be displayed. The appended characters d, o, and x specify the display base as decimal, octal or hexadecimal respectively. _A[dox] Identical to the _a conversion string except that it is only performed once, when all of the input data has been processed. _c Output characters in the default character set. Nonprinting characters are displayed in three character, zero-padded octal, except for those representable by standard escape notation (see above), which are displayed as two character strings. _p Output characters in the default character set. Nonprinting characters are displayed as a single ``.''. _u Output US ASCII characters, with the exception that control characters are displayed using the following, lower-case, names. Characters greater than 0xff, hexadecimal, are displayed as hexadecimal strings. 000 NUL 001 SOH 002 STX 003 ETX 004 EOT 005 ENQ 006 ACK 007 BEL 008 BS 009 HT 00A LF 00B VT 00C FF 00D CR 00E SO 00F SI 010 DLE 011 DC1 012 DC2 013 DC3 014 DC4 015 NAK 016 SYN 017 ETB 018 CAN 019 EM 01A SUB 01B ESC 01C FS 01D GS 01E RS 01F US 07F DEL The default and supported byte counts for the conversion characters are as follows: %_c, %_p, %_u, %c One byte counts only. %d, %i, %o, %u, %X, %x Four byte default, one, two and four byte counts supported. %E, %e, %f, %G, %g Eight byte default, four and twelve byte counts supported. The amount of data interpreted by each format string is the sum of the data required by each format unit, which is the iteration count times the byte count, or the iteration count times the number of bytes required by the format if the byte count is not specified. The input is manipulated in ``blocks'', where a block is defined as the largest amount of data specified by any format string. Format strings interpreting less than an input block's worth of data, whose last format unit both interprets some number of bytes and does not have a specified iteration count, have the iteration count incremented until the entire input block has been processed or there is not enough data remaining in the block to satisfy the format string. If, either as a result of user specification or hexdump modifying the iteration count as described above, an iteration count is greater than one, no trailing whitespace characters are output during the last iteration. It is an error to specify a byte count as well as multiple conversion characters or strings unless all but one of the conversion characters or strings is _a or _A. If, as a result of the specification of the -n option or end-of-file being reached, input data only partially satisfies a format string, the input block is zero-padded sufficiently to display all available data (i.e., any format units overlapping the end of data will display some number of the zero bytes). Further output by such format strings is replaced by an equivalent number of spaces. An equivalent number of spaces is defined as the number of spaces output by an s conversion character with the same field width and precision as the original conversion character or conversion string but with any ``+'', `` '', ``#'' conversion flag characters removed, and referencing a NULL string. If no format strings are specified, the default display is equivalent to specifying the -x option. EXIT STATUS
The hexdump and hd utilities exit 0 on success, and >0 if an error occurs. EXAMPLES
Display the input in perusal format: "%06.6_ao " 12/1 "%3_u " " " "%_p " " " Implement the -x option: "%07.7_Ax " "%07.7_ax " 8/2 "%04x " " " Some examples for the -e option: # hex bytes % echo hello | hexdump -v -e '/1 "%02X "' ; echo 68 65 6C 6C 6F 0A # same, with ASCII section % echo hello | hexdump -e '8/1 "%02X "" "" "' -e '8/1 "%c"" "' 68 65 6C 6C 6F 0A hello # hex with preceding 'x' % echo hello | hexdump -v -e '"x" 1/1 "%02X" " "' ; echo x68 x65 x6C x6C x6F x0A # one hex byte per line % echo hello | hexdump -v -e '/1 "%02X "' 68 65 6C 6C 6F 0A # a table of byte#, hex, decimal, octal, ASCII % echo hello | hexdump -v -e '/1 "%_ad# "' -e '/1 "%02X hex"' -e '/1 " = %03i dec"' -e '/1 " = %03o oct"' -e '/1 " = _%c\_ "' 0# 68 hex = 104 dec = 150 oct = _h_ 1# 65 hex = 101 dec = 145 oct = _e_ 2# 6C hex = 108 dec = 154 oct = _l_ 3# 6C hex = 108 dec = 154 oct = _l_ 4# 6F hex = 111 dec = 157 oct = _o_ 5# 0A hex = 010 dec = 012 oct = _ _ # byte# & ASCII with control chars % echo hello | hexdump -v -e '/1 "%_ad# "' -e '/1 " _%_u\_ "' 0# _h_ 1# _e_ 2# _l_ 3# _l_ 4# _o_ 5# _lf_ SEE ALSO
gdb(1), od(1) BSD
February 18, 2010 BSD

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