1.\" Copyright (c) 1989, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)hexdump.1 8.2 (Berkeley) 4/18/94 33.\" $FreeBSD: src/usr.bin/hexdump/hexdump.1,v 1.9.2.9 2003/02/25 20:05:17 trhodes Exp $ 34.\" $DragonFly: src/usr.bin/hexdump/hexdump.1,v 1.2 2003/06/17 04:29:27 dillon Exp $ 35.\" 36.Dd April 18, 1994 37.Dt HEXDUMP 1 38.Os 39.Sh NAME 40.Nm hexdump , hd 41.Nd ASCII, decimal, hexadecimal, octal dump 42.Sh SYNOPSIS 43.Nm 44.Op Fl bcCdovx 45.Op Fl e Ar format_string 46.Op Fl f Ar format_file 47.Op Fl n Ar length 48.Bk -words 49.Op Fl s Ar skip 50.Ek 51.Ar 52.Nm hd 53.Op Fl bcdovx 54.Op Fl e Ar format_string 55.Op Fl f Ar format_file 56.Op Fl n Ar length 57.Bk -words 58.Op Fl s Ar skip 59.Ek 60.Ar 61.Sh DESCRIPTION 62The 63.Nm 64utility is a filter which displays the specified files, or 65the standard input, if no files are specified, in a user specified 66format. 67.Pp 68The options are as follows: 69.Bl -tag -width indent 70.It Fl b 71.Em One-byte octal display . 72Display the input offset in hexadecimal, followed by sixteen 73space-separated, three column, zero-filled, bytes of input data, 74in octal, per line. 75.It Fl c 76.Em One-byte character display . 77Display the input offset in hexadecimal, followed by sixteen 78space-separated, three column, space-filled, characters of input 79data per line. 80.It Fl C 81.Em Canonical hex+ASCII display . 82Display the input offset in hexadecimal, followed by sixteen 83space-separated, two column, hexadecimal bytes, followed by the 84same sixteen bytes in %_p format enclosed in ``|'' characters. 85.Pp 86Calling the command 87.Nm hd 88implies this option. 89.It Fl d 90.Em Two-byte decimal display . 91Display the input offset in hexadecimal, followed by eight 92space-separated, five column, zero-filled, two-byte units 93of input data, in unsigned decimal, per line. 94.It Fl e Ar format_string 95Specify a format string to be used for displaying data. 96.It Fl f Ar format_file 97Specify a file that contains one or more newline separated format strings. 98Empty lines and lines whose first non-blank character is a hash mark 99.Pf ( Cm \&# ) 100are ignored. 101.It Fl n Ar length 102Interpret only 103.Ar length 104bytes of input. 105.It Fl o 106.Em Two-byte octal display . 107Display the input offset in hexadecimal, followed by eight 108space-separated, six column, zero-filled, two byte quantities of 109input data, in octal, per line. 110.It Fl s Ar offset 111Skip 112.Ar offset 113bytes from the beginning of the input. 114By default, 115.Ar offset 116is interpreted as a decimal number. 117With a leading 118.Cm 0x 119or 120.Cm 0X , 121.Ar offset 122is interpreted as a hexadecimal number, 123otherwise, with a leading 124.Cm 0 , 125.Ar offset 126is interpreted as an octal number. 127Appending the character 128.Cm b , 129.Cm k , 130or 131.Cm m 132to 133.Ar offset 134causes it to be interpreted as a multiple of 135.Li 512 , 136.Li 1024 , 137or 138.Li 1048576 , 139respectively. 140.It Fl v 141Cause 142.Nm 143to display all input data. 144Without the 145.Fl v 146option, any number of groups of output lines, which would be 147identical to the immediately preceding group of output lines (except 148for the input offsets), are replaced with a line comprised of a 149single asterisk. 150.It Fl x 151.Em Two-byte hexadecimal display . 152Display the input offset in hexadecimal, followed by eight, space 153separated, four column, zero-filled, two-byte quantities of input 154data, in hexadecimal, per line. 155.El 156.Pp 157For each input file, 158.Nm 159sequentially copies the input to standard output, transforming the 160data according to the format strings specified by the 161.Fl e 162and 163.Fl f 164options, in the order that they were specified. 165.Ss Formats 166A format string contains any number of format units, separated by 167whitespace. 168A format unit contains up to three items: an iteration count, a byte 169count, and a format. 170.Pp 171The iteration count is an optional positive integer, which defaults to 172one. 173Each format is applied iteration count times. 174.Pp 175The byte count is an optional positive integer. 176If specified it defines the number of bytes to be interpreted by 177each iteration of the format. 178.Pp 179If an iteration count and/or a byte count is specified, a single slash 180must be placed after the iteration count and/or before the byte count 181to disambiguate them. 182Any whitespace before or after the slash is ignored. 183.Pp 184The format is required and must be surrounded by double quote 185(" ") marks. 186It is interpreted as a fprintf-style format string (see 187.Xr fprintf 3 ) , 188with the 189following exceptions: 190.Bl -bullet -offset indent 191.It 192An asterisk (*) may not be used as a field width or precision. 193.It 194A byte count or field precision 195.Em is 196required for each ``s'' conversion 197character (unlike the 198.Xr fprintf 3 199default which prints the entire string if the precision is unspecified). 200.It 201The conversion characters ``h'', ``l'', ``n'', ``p'' and ``q'' are 202not supported. 203.It 204The single character escape sequences 205described in the C standard are supported: 206.Bd -ragged -offset indent -compact 207.Bl -column <alert_character> 208.It "NUL \e0 209.It "<alert character> \ea 210.It "<backspace> \eb 211.It "<form-feed> \ef 212.It "<newline> \en 213.It "<carriage return> \er 214.It "<tab> \et 215.It "<vertical tab> \ev 216.El 217.Ed 218.El 219.Pp 220The 221.Nm 222utility also supports the following additional conversion strings: 223.Bl -tag -width Fl 224.It Cm \&_a Ns Op Cm dox 225Display the input offset, cumulative across input files, of the 226next byte to be displayed. 227The appended characters 228.Cm d , 229.Cm o , 230and 231.Cm x 232specify the display base 233as decimal, octal or hexadecimal respectively. 234.It Cm \&_A Ns Op Cm dox 235Identical to the 236.Cm \&_a 237conversion string except that it is only performed 238once, when all of the input data has been processed. 239.It Cm \&_c 240Output characters in the default character set. 241Nonprinting characters are displayed in three character, zero-padded 242octal, except for those representable by standard escape notation 243(see above), 244which are displayed as two character strings. 245.It Cm _p 246Output characters in the default character set. 247Nonprinting characters are displayed as a single 248.Dq Cm \&. . 249.It Cm _u 250Output US 251.Tn ASCII 252characters, with the exception that control characters are 253displayed using the following, lower-case, names. 254Characters greater than 0xff, hexadecimal, are displayed as hexadecimal 255strings. 256.Bl -column \&000_nu \&001_so \&002_st \&003_et \&004_eo 257.It "\&000\ NUL\t001\ SOH\t002\ STX\t003\ ETX\t004\ EOT\t005\ ENQ 258.It "\&006\ ACK\t007\ BEL\t008\ BS\t009\ HT\t00A\ LF\t00B\ VT 259.It "\&00C\ FF\t00D\ CR\t00E\ SO\t00F\ SI\t010\ DLE\t011\ DC1 260.It "\&012\ DC2\t013\ DC3\t014\ DC4\t015\ NAK\t016\ SYN\t017\ ETB 261.It "\&018\ CAN\t019\ EM\t01A\ SUB\t01B\ ESC\t01C\ FS\t01D\ GS 262.It "\&01E\ RS\t01F\ US\t0FF\ DEL 263.El 264.El 265.Pp 266The default and supported byte counts for the conversion characters 267are as follows: 268.Bl -tag -width "Xc,_Xc,_Xc,_Xc,_Xc,_Xc" -offset indent 269.It Li \&%_c , \&%_p , \&%_u , \&%c 270One byte counts only. 271.It Xo 272.Li \&%d , \&%i , \&%o , 273.Li \&%u , \&%X , \&%x 274.Xc 275Four byte default, one, two and four byte counts supported. 276.It Xo 277.Li \&%E , \&%e , \&%f , 278.Li \&%G , \&%g 279.Xc 280Eight byte default, four and twelve byte counts supported. 281.El 282.Pp 283The amount of data interpreted by each format string is the sum of the 284data required by each format unit, which is the iteration count times the 285byte count, or the iteration count times the number of bytes required by 286the format if the byte count is not specified. 287.Pp 288The input is manipulated in ``blocks'', where a block is defined as the 289largest amount of data specified by any format string. 290Format strings interpreting less than an input block's worth of data, 291whose last format unit both interprets some number of bytes and does 292not have a specified iteration count, have the iteration count 293incremented until the entire input block has been processed or there 294is not enough data remaining in the block to satisfy the format string. 295.Pp 296If, either as a result of user specification or 297.Nm 298modifying 299the iteration count as described above, an iteration count is 300greater than one, no trailing whitespace characters are output 301during the last iteration. 302.Pp 303It is an error to specify a byte count as well as multiple conversion 304characters or strings unless all but one of the conversion characters 305or strings is 306.Cm \&_a 307or 308.Cm \&_A . 309.Pp 310If, as a result of the specification of the 311.Fl n 312option or end-of-file being reached, input data only partially 313satisfies a format string, the input block is zero-padded sufficiently 314to display all available data (i.e. any format units overlapping the 315end of data will display some number of the zero bytes). 316.Pp 317Further output by such format strings is replaced by an equivalent 318number of spaces. 319An equivalent number of spaces is defined as the number of spaces 320output by an 321.Cm s 322conversion character with the same field width 323and precision as the original conversion character or conversion 324string but with any 325.Dq Li \&+ , 326.Dq \&\ \& , 327.Dq Li \&# 328conversion flag characters 329removed, and referencing a NULL string. 330.Pp 331If no format strings are specified, the default display is equivalent 332to specifying the 333.Fl x 334option. 335.Sh DIAGNOSTICS 336.Ex -std hexdump hd 337.Sh EXAMPLES 338Display the input in perusal format: 339.Bd -literal -offset indent 340"%06.6_ao " 12/1 "%3_u " 341"\et\et" "%_p " 342"\en" 343.Ed 344.Pp 345Implement the \-x option: 346.Bd -literal -offset indent 347"%07.7_Ax\en" 348"%07.7_ax " 8/2 "%04x " "\en" 349.Ed 350.Sh SEE ALSO 351.Xr gdb 1 352