{ "mode": "man", "parameter": "XXD", "section": "1", "url": "https://www.chedong.com/phpMan.php/man/XXD/1/json", "generated": "2026-06-15T13:13:10Z", "synopsis": "xxd -h[elp]\nxxd [options] [infile [outfile]]\nxxd -r[evert] [options] [infile [outfile]]", "sections": { "NAME": { "content": "xxd - make a hexdump or do the reverse.\n", "subsections": [] }, "SYNOPSIS": { "content": "xxd -h[elp]\nxxd [options] [infile [outfile]]\nxxd -r[evert] [options] [infile [outfile]]\n", "subsections": [] }, "DESCRIPTION": { "content": "xxd creates a hex dump of a given file or standard input. It can also convert a hex dump\nback to its original binary form. Like uuencode(1) and uudecode(1) it allows the transmis‐\nsion of binary data in a `mail-safe' ASCII representation, but has the advantage of decoding\nto standard output. Moreover, it can be used to perform binary file patching.\n", "subsections": [] }, "OPTIONS": { "content": "If no infile is given, standard input is read. If infile is specified as a `-' character,\nthen input is taken from standard input. If no outfile is given (or a `-' character is in\nits place), results are sent to standard output.\n\nNote that a \"lazy\" parser is used which does not check for more than the first option letter,\nunless the option is followed by a parameter. Spaces between a single option letter and its\nparameter are optional. Parameters to options can be specified in decimal, hexadecimal or\noctal notation. Thus -c8, -c 8, -c 010 and -cols 8 are all equivalent.\n\n-a | -autoskip\nToggle autoskip: A single '*' replaces nul-lines. Default off.\n\n-b | -bits\nSwitch to bits (binary digits) dump, rather than hexdump. This option writes octets\nas eight digits \"1\"s and \"0\"s instead of a normal hexadecimal dump. Each line is pre‐\nceded by a line number in hexadecimal and followed by an ascii (or ebcdic) representa‐\ntion. The command line switches -r, -p, -i do not work with this mode.\n\n-c cols | -cols cols\nFormat octets per line. Default 16 (-i: 12, -ps: 30, -b: 6). Max 256.\n\n-C | -capitalize\nCapitalize variable names in C include file style, when using -i.\n\n-E | -EBCDIC\nChange the character encoding in the righthand column from ASCII to EBCDIC. This does\nnot change the hexadecimal representation. The option is meaningless in combinations\nwith -r, -p or -i.\n\n-e Switch to little-endian hexdump. This option treats byte groups as words in little-\nendian byte order. The default grouping of 4 bytes may be changed using -g. This op‐\ntion only applies to hexdump, leaving the ASCII (or EBCDIC) representation unchanged.\nThe command line switches -r, -p, -i do not work with this mode.\n\n-g bytes | -groupsize bytes\nSeparate the output of every bytes (two hex characters or eight bit-digits\neach) by a whitespace. Specify -g 0 to suppress grouping. defaults to 2 in\nnormal mode, 4 in little-endian mode and 1 in bits mode. Grouping does not apply to\npostscript or include style.\n\n-h | -help\nPrint a summary of available commands and exit. No hex dumping is performed.\n\n-i | -include\nOutput in C include file style. A complete static array definition is written (named\nafter the input file), unless xxd reads from stdin.\n\n-l len | -len len\nStop after writing octets.\n\n-o offset\nAdd to the displayed file position.\n\n-p | -ps | -postscript | -plain\nOutput in postscript continuous hexdump style. Also known as plain hexdump style.\n\n-r | -revert\nReverse operation: convert (or patch) hexdump into binary. If not writing to stdout,\nxxd writes into its output file without truncating it. Use the combination -r -p to\nread plain hexadecimal dumps without line number information and without a particular\ncolumn layout. Additional Whitespace and line-breaks are allowed anywhere.\n\n-seek offset\nWhen used after -r: revert with added to file positions found in hexdump.\n\n-s [+][-]seek\nStart at bytes abs. (or rel.) infile offset. + indicates that the seek is rel‐\native to the current stdin file position (meaningless when not reading from stdin). -\nindicates that the seek should be that many characters from the end of the input (or\nif combined with +: before the current stdin file position). Without -s option, xxd\nstarts at the current file position.\n\n-u Use upper case hex letters. Default is lower case.\n\n-v | -version\nShow version string.\n", "subsections": [] }, "CAVEATS": { "content": "xxd -r has some builtin magic while evaluating line number information. If the output file\nis seekable, then the linenumbers at the start of each hexdump line may be out of order,\nlines may be missing, or overlapping. In these cases xxd will lseek(2) to the next position.\nIf the output file is not seekable, only gaps are allowed, which will be filled by null-\nbytes.\n\nxxd -r never generates parse errors. Garbage is silently skipped.\n\nWhen editing hexdumps, please note that xxd -r skips everything on the input line after read‐\ning enough columns of hexadecimal data (see option -c). This also means, that changes to the\nprintable ascii (or ebcdic) columns are always ignored. Reverting a plain (or postscript)\nstyle hexdump with xxd -r -p does not depend on the correct number of columns. Here anything\nthat looks like a pair of hex-digits is interpreted.\n\nNote the difference between\n% xxd -i file\nand\n% xxd -i < file\n\nxxd -s +seek may be different from xxd -s seek, as lseek(2) is used to \"rewind\" input. A '+'\nmakes a difference if the input source is stdin, and if stdin's file position is not at the\nstart of the file by the time xxd is started and given its input. The following examples may\nhelp to clarify (or further confuse!)...\n\nRewind stdin before reading; needed because the `cat' has already read to the end of stdin.\n% sh -c \"cat > plaincopy; xxd -s 0 > hexcopy\" < file\n\nHexdump from file position 0x480 (=1024+128) onwards. The `+' sign means \"relative to the\ncurrent position\", thus the `128' adds to the 1k where dd left off.\n% sh -c \"dd of=plainsnippet bs=1k count=1; xxd -s +128 > hexsnippet\" < file\n\nHexdump from file position 0x100 ( = 1024-768) on.\n% sh -c \"dd of=plainsnippet bs=1k count=1; xxd -s +-768 > hexsnippet\" < file\n\nHowever, this is a rare situation and the use of `+' is rarely needed. The author prefers to\nmonitor the effect of xxd with strace(1) or truss(1), whenever -s is used.\n", "subsections": [] }, "EXAMPLES": { "content": "Print everything but the first three lines (hex 0x30 bytes) of file.\n% xxd -s 0x30 file\n\nPrint 3 lines (hex 0x30 bytes) from the end of file.\n% xxd -s -0x30 file\n\nPrint 120 bytes as continuous hexdump with 20 octets per line.\n% xxd -l 120 -ps -c 20 xxd.1\n2e54482058584420312022417567757374203139\n39362220224d616e75616c207061676520666f72\n20787864220a2e5c220a2e5c222032317374204d\n617920313939360a2e5c22204d616e2070616765\n20617574686f723a0a2e5c2220202020546f6e79\n204e7567656e74203c746f6e79407363746e7567\n\nHexdump the first 120 bytes of this man page with 12 octets per line.\n% xxd -l 120 -c 12 xxd.1\n0000000: 2e54 4820 5858 4420 3120 2241 .TH XXD 1 \"A\n000000c: 7567 7573 7420 3139 3936 2220 ugust 1996\"\n0000018: 224d 616e 7561 6c20 7061 6765 \"Manual page\n0000024: 2066 6f72 2078 7864 220a 2e5c for xxd\"..\\\n0000030: 220a 2e5c 2220 3231 7374 204d \"..\\\" 21st M\n000003c: 6179 2031 3939 360a 2e5c 2220 ay 1996..\\\"\n0000048: 4d61 6e20 7061 6765 2061 7574 Man page aut\n0000054: 686f 723a 0a2e 5c22 2020 2020 hor:..\\\"\n0000060: 546f 6e79 204e 7567 656e 7420 Tony Nugent\n000006c: 3c74 6f6e 7940 7363 746e 7567 outputfile\n\nPatch the date in the file xxd.1\n% echo \"0000037: 3574 68\" | xxd -r - xxd.1\n% xxd -s 0x36 -l 13 -c 13 xxd.1\n0000036: 3235 7468 204d 6179 2031 3939 36 25th May 1996\n\nCreate a 65537 byte file with all bytes 0x00, except for the last one which is 'A' (hex\n0x41).\n% echo \"010000: 41\" | xxd -r > file\n\nHexdump this file with autoskip.\n% xxd -a -c 12 file\n0000000: 0000 0000 0000 0000 0000 0000 ............\n*\n000fffc: 0000 0000 40 ....A\n\nCreate a 1 byte file containing a single 'A' character. The number after '-r -s' adds to the\nlinenumbers found in the file; in effect, the leading bytes are suppressed.\n% echo \"010000: 41\" | xxd -r -s -0x10000 > file\n\nUse xxd as a filter within an editor such as vim(1) to hexdump a region marked between `a'\nand `z'.\n:'a,'z!xxd\n\nUse xxd as a filter within an editor such as vim(1) to recover a binary hexdump marked be‐\ntween `a' and `z'.\n:'a,'z!xxd -r\n\nUse xxd as a filter within an editor such as vim(1) to recover one line of a hexdump. Move\nthe cursor over the line and type:\n!!xxd -r\n\nRead single characters from a serial line\n% xxd -c1 < /dev/term/b &\n% stty < /dev/term/b -echo -opost -isig -icanon min 1\n% echo -n foo > /dev/term/b\n", "subsections": [] }, "RETURN VALUES": { "content": "The following error values are returned:\n\n0 no errors encountered.\n\n-1 operation not supported ( xxd -r -i still impossible).\n\n1 error while parsing options.\n\n2 problems with input file.\n\n3 problems with output file.\n\n4,5 desired seek position is unreachable.\n", "subsections": [] }, "SEE ALSO": { "content": "uuencode(1), uudecode(1), patch(1)\n", "subsections": [] }, "WARNINGS": { "content": "The tools weirdness matches its creators brain. Use entirely at your own risk. Copy files.\nTrace it. Become a wizard.\n", "subsections": [] }, "VERSION": { "content": "This manual page documents xxd version 1.7\n", "subsections": [] }, "AUTHOR": { "content": "(c) 1990-1997 by Juergen Weigert\n\n\nDistribute freely and credit me,\nmake money and share with me,\nlose money and don't ask me.\n\nManual page started by Tony Nugent\n \nSmall changes by Bram Moolenaar. Edited by Juergen Weigert.\n\nManual page for xxd August 1996 XXD(1)", "subsections": [] } }, "summary": "xxd - make a hexdump or do the reverse.", "flags": [], "examples": [ "Print everything but the first three lines (hex 0x30 bytes) of file.", "% xxd -s 0x30 file", "Print 3 lines (hex 0x30 bytes) from the end of file.", "% xxd -s -0x30 file", "Print 120 bytes as continuous hexdump with 20 octets per line.", "% xxd -l 120 -ps -c 20 xxd.1", "2e54482058584420312022417567757374203139", "39362220224d616e75616c207061676520666f72", "20787864220a2e5c220a2e5c222032317374204d", "617920313939360a2e5c22204d616e2070616765", "20617574686f723a0a2e5c2220202020546f6e79", "204e7567656e74203c746f6e79407363746e7567", "Hexdump the first 120 bytes of this man page with 12 octets per line.", "% xxd -l 120 -c 12 xxd.1", "0000000: 2e54 4820 5858 4420 3120 2241 .TH XXD 1 \"A", "000000c: 7567 7573 7420 3139 3936 2220 ugust 1996\"", "0000018: 224d 616e 7561 6c20 7061 6765 \"Manual page", "0000024: 2066 6f72 2078 7864 220a 2e5c for xxd\"..\\", "0000030: 220a 2e5c 2220 3231 7374 204d \"..\\\" 21st M", "000003c: 6179 2031 3939 360a 2e5c 2220 ay 1996..\\\"", "0000048: 4d61 6e20 7061 6765 2061 7574 Man page aut", "0000054: 686f 723a 0a2e 5c22 2020 2020 hor:..\\\"", "0000060: 546f 6e79 204e 7567 656e 7420 Tony Nugent", "000006c: 3c74 6f6e 7940 7363 746e 7567 outputfile", "Patch the date in the file xxd.1", "% echo \"0000037: 3574 68\" | xxd -r - xxd.1", "% xxd -s 0x36 -l 13 -c 13 xxd.1", "0000036: 3235 7468 204d 6179 2031 3939 36 25th May 1996", "Create a 65537 byte file with all bytes 0x00, except for the last one which is 'A' (hex", "0x41).", "% echo \"010000: 41\" | xxd -r > file", "Hexdump this file with autoskip.", "% xxd -a -c 12 file", "0000000: 0000 0000 0000 0000 0000 0000 ............", "000fffc: 0000 0000 40 ....A", "Create a 1 byte file containing a single 'A' character. The number after '-r -s' adds to the", "linenumbers found in the file; in effect, the leading bytes are suppressed.", "% echo \"010000: 41\" | xxd -r -s -0x10000 > file", "Use xxd as a filter within an editor such as vim(1) to hexdump a region marked between `a'", "and `z'.", ":'a,'z!xxd", "Use xxd as a filter within an editor such as vim(1) to recover a binary hexdump marked be‐", "tween `a' and `z'.", ":'a,'z!xxd -r", "Use xxd as a filter within an editor such as vim(1) to recover one line of a hexdump. Move", "the cursor over the line and type:", "!!xxd -r", "Read single characters from a serial line", "% xxd -c1 < /dev/term/b &", "% stty < /dev/term/b -echo -opost -isig -icanon min 1", "% echo -n foo > /dev/term/b" ], "see_also": [ { "name": "uuencode", "section": "1", "url": "https://www.chedong.com/phpMan.php/man/uuencode/1/json" }, { "name": "uudecode", "section": "1", "url": "https://www.chedong.com/phpMan.php/man/uudecode/1/json" }, { "name": "patch", "section": "1", "url": "https://www.chedong.com/phpMan.php/man/patch/1/json" } ], "tldr": { "source": "official", "description": "Create a hexadecimal representation (hexdump) from a binary file, or vice-versa.", "examples": [ { "description": "Generate a hexdump from a binary file and display the output", "command": "xxd {{input_file}}" }, { "description": "Generate a hexdump from a binary file and save it as a text file", "command": "xxd {{input_file}} {{output_file}}" }, { "description": "Display a more compact output, replacing consecutive zeros (if any) with a star", "command": "xxd {{-a|-autoskip}} {{input_file}}" }, { "description": "Display the output with 10 columns of one octet (byte) each", "command": "xxd {{-c|-cols}} {{10}} {{input_file}}" }, { "description": "Display output only up to a length of 32 bytes", "command": "xxd {{-l|-len}} {{32}} {{input_file}}" }, { "description": "Display the output in plain mode, without any gaps between the columns", "command": "xxd {{-p|-postscript}} {{input_file}}" }, { "description": "Revert a plaintext hexdump back into binary, and save it as a binary file", "command": "xxd {{-r|-revert}} {{-p|-postscript}} {{input_file}} {{output_file}}" } ] } }