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diff --git a/mnv/runtime/doc/xxd.man b/mnv/runtime/doc/xxd.man new file mode 100644 index 0000000000..bb52d6f46c --- /dev/null +++ b/mnv/runtime/doc/xxd.man @@ -0,0 +1,293 @@ +XXD(1) General Commands Manual XXD(1) + +NAME + xxd - make a hex dump or do the reverse. + +SYNOPSIS + xxd -h[elp] + xxd [options] [infile [outfile]] + xxd -r[evert] [options] [infile [outfile]] + +DESCRIPTION + xxd creates a hex dump of a given file or standard input. It can also con‐ + vert a hex dump back to its original binary form. Like uuencode(1) and + uudecode(1) it allows the transmission of binary data in a ‘mail-safe' + ASCII representation, but has the advantage of decoding to standard output. + Moreover, it can be used to perform binary file patching. + +OPTIONS + If no infile is given, standard input is read. If infile is specified as a + `-' character, then input is taken from standard input. If no outfile is + given (or a `-' character is in its place), results are sent to standard + output. + + Note that a "lazy" parser is used which does not check for more than the + first option letter, unless the option is followed by a parameter. Spaces + between a single option letter and its parameter are optional. Parameters + to options can be specified in decimal, hexadecimal or octal notation. + Thus -c8, -c 8, -c 010 and -cols 8 are all equivalent. + + -a | -autoskip + Toggle autoskip: A single '*' replaces NUL-lines. Default off. + + -b | -bits + Switch to bits (binary digits) dump, rather than hex dump. This op‐ + tion writes octets as eight digits "1"s and "0"s instead of a normal + hexadecimal dump. Each line is preceded by a line number in hexadec‐ + imal and followed by an ASCII (or EBCDIC) representation. The com‐ + mand line switch -p does not work with this mode. Can be combined + with -i. + + -c cols | -cols cols + Format <cols> octets per line. Default 16 (-i: 12, -ps: 30, -b: 6). + Max 256. No maximum for -ps. With -ps, 0 results in one long line + of output. + + -C | -capitalize + Capitalize variable names in C include file style, when using -i. + + -d show offset in decimal instead of hex. + + -E | -EBCDIC + Change the character encoding in the righthand column from ASCII to + EBCDIC. This does not change the hexadecimal representation. The + option is meaningless in combinations with -r, -p or -i. + + -e Switch to little-endian hex dump. This option treats byte groups as + words in little-endian byte order. The default grouping of 4 bytes + may be changed using -g. This option only applies to the hex dump, + leaving the ASCII (or EBCDIC) representation unchanged. The command + line switches -r, -p, -i do not work with this mode. + + -g bytes | -groupsize bytes + Separate the output of every <bytes> bytes (two hex characters or + eight bit digits each) by a whitespace. Specify -g 0 to suppress + grouping. <Bytes> defaults to 2 in normal mode, 4 in little-endian + mode and 1 in bits mode. Grouping does not apply to PostScript or + include style. + + -h | -help + Print a summary of available commands and exit. No hex dumping is + performed. + + -i | -include + Output in C include file style. A complete static array definition + is written (named after the input file), unless xxd reads from + stdin. Can be combined with -b. + + -l len | -len len + Stop after writing <len> octets. + + -n name | -name name + Override the variable name output when -i is used. The array is + named name and the length is named name_len. + + -o offset + Add <offset> to the displayed file position. + + -p | -ps | -postscript | -plain + Output in PostScript continuous hex dump style. Also known as plain + hex dump style. + + -r | -revert + Reverse operation: convert (or patch) hex dump into binary. If not + writing to stdout, xxd writes into its output file without truncat‐ + ing it. Use the combination -r -p to read plain hexadecimal dumps + without line number information and without a particular column lay‐ + out. Additional whitespace and line breaks are allowed anywhere. Use + the combination -r -b to read a bits dump instead of a hex dump. + + -R when + In the output the hex-value and the value are both colored with the + same color depending on the hex-value. Mostly helping to differenti‐ + ate printable and non-printable characters. when is never, always, + or auto (default: auto). When the $NO_COLOR environment variable is + set, colorization will be disabled. + + -seek offset + When used after -r: revert with <offset> added to file positions + found in hex dump. + + -s [+][-]seek + Start at <seek> bytes abs. (or rel.) infile offset. + indicates + that the seek is relative to the current stdin file position (mean‐ + ingless when not reading from stdin). - indicates that the seek + should be that many characters from the end of the input (or if com‐ + bined with +: before the current stdin file position). Without -s + option, xxd starts at the current file position. + + -t When outputting in C include file style using -i include the termi‐ + nating zero. + + -u Use upper-case hex letters. Default is lower-case. + + -v | -version + Show version string. + +CAVEATS + xxd -r has some built-in magic while evaluating line number information. + If the output file is seekable, then the line numbers at the start of each + hex dump line may be out of order, lines may be missing, or overlapping. In + these cases xxd will lseek(2) to the next position. If the output file is + not seekable, only gaps are allowed, which will be filled by null-bytes. + + xxd -r never generates parse errors. Garbage is silently skipped. + + When editing hex dumps, please note that xxd -r skips everything on the in‐ + put line after reading enough columns of hexadecimal data (see option -c). + This also means that changes to the printable ASCII (or EBCDIC) columns are + always ignored. Reverting a plain (or PostScript) style hex dump with xxd + -r -p does not depend on the correct number of columns. Here, anything + that looks like a pair of hex digits is interpreted. + + Note the difference between + % xxd -i file + and + % xxd -i < file + + xxd -s +seek may be different from xxd -s seek, as lseek(2) is used to + "rewind" input. A '+' makes a difference if the input source is stdin, and + if stdin's file position is not at the start of the file by the time xxd is + started and given its input. The following examples may help to clarify + (or further confuse!): + + Rewind stdin before reading; needed because the ‘cat' has already read to + the end of stdin. + % sh -c "cat > plain_copy; xxd -s 0 > hex_copy" < file + + Hex dump from file position 0x480 (=1024+128) onwards. The ‘+' sign means + "relative to the current position", thus the ‘128' adds to the 1k where dd + left off. + % sh -c "dd of=plain_snippet bs=1k count=1; xxd -s +128 > hex_snippet" < + file + + Hex dump from file position 0x100 (=1024-768) onwards. + % sh -c "dd of=plain_snippet bs=1k count=1; xxd -s +-768 > hex_snippet" < + file + + However, this is a rare situation and the use of ‘+' is rarely needed. The + author prefers to monitor the effect of xxd with strace(1) or truss(1), + whenever -s is used. + +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 + + Note: The results of the examples below are relevant to the xxd.1 man page + as of March 2026 + + Print 120 bytes as a continuous hex dump with 20 octets per line. + % xxd -l 120 -ps -c 20 xxd.1 + 2e544820585844203120224d6172203230323622 + 20224d616e75616c207061676520666f72207878 + 64220a2e5c220a2e5c222032317374204d617920 + 313939360a2e5c22204d616e2070616765206175 + 74686f723a0a2e5c2220202020546f6e79204e75 + 67656e74203c746f6e79407363746e7567656e2e + + Hex dump the first 120 bytes of this man page with 12 octets per line. + % xxd -l 120 -c 12 xxd.1 + 00000000: 2e54 4820 5858 4420 3120 224d .TH XXD 1 "M + 0000000c: 6172 2032 3032 3622 2022 4d61 ar 2026" "Ma + 00000018: 6e75 616c 2070 6167 6520 666f nual page fo + 00000024: 7220 7878 6422 0a2e 5c22 0a2e r xxd"..\".. + 00000030: 5c22 2032 3173 7420 4d61 7920 \" 21st May + 0000003c: 3139 3936 0a2e 5c22 204d 616e 1996..\" Man + 00000048: 2070 6167 6520 6175 7468 6f72 page author + 00000054: 3a0a 2e5c 2220 2020 2054 6f6e :..\" Ton + 00000060: 7920 4e75 6765 6e74 203c 746f y Nugent <to + 0000006c: 6e79 4073 6374 6e75 6765 6e2e ny@sctnugen. + + Display just the date from the file xxd.1 + % xxd -s 0x33 -l 13 -c 13 xxd.1 + 00000033: 3231 7374 204d 6179 2031 3939 36 21st May 1996 + + Copy input_file to output_file and prepend 100 bytes of value 0x00. + % xxd input_file | xxd -r -s 100 > output_file + + Patch the date in the file xxd.1 + % echo "0000034: 3574 68" | xxd -r - xxd.1 + % xxd -s 0x33 -l 13 -c 13 xxd.1 + 00000033: 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 + + Hex dump this file with autoskip. + % xxd -a -c 12 file + 00000000: 0000 0000 0000 0000 0000 0000 ............ + * + 0000fffc: 0000 0000 41 ....A + + Create a 1 byte file containing a single 'A' character. The number after + '-r -s' adds to the line numbers 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 mnv(1) to hex dump a region + marked between ‘a' and ‘z'. + :'a,'z!xxd + + Use xxd as a filter within an editor such as mnv(1) to recover a binary hex + dump marked between ‘a' and ‘z'. + :'a,'z!xxd -r + + Use xxd as a filter within an editor such as mnv(1) to recover one line of + a hex dump. 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 + + Output in C style include output with terminating zero + % echo -n "0123456789" > digits + % xxd -i -t digits + unsigned char digits[] = { + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x00 + }; + unsigned int digits_len = 10; + +RETURN VALUES + The following error values are returned: + + 0 no errors encountered. + + -1 operation not supported (xxd -r -i still impossible). + + 1 error while parsing options. + + 2 problems with input file. + + 3 problems with output file. + + 4,5 desired seek position is unreachable. + +SEE ALSO + uuencode(1), uudecode(1), patch(1) + +WARNINGS + The tool's weirdness matches its creator's brain. Use entirely at your own + risk. Copy files. Trace it. Become a wizard. + +VERSION + This manual page documents xxd version 1.7 from 2024-05. + +AUTHOR + (c) 1990-1997 by Juergen Weigert + <jnweiger@informatik.uni-erlangen.de> + + Distribute freely and credit me, + make money and share with me, + lose money and don't ask me. + + Manual page started by Tony Nugent + <tony@sctnugen.ppp.gu.edu.au> <T.Nugent@sct.gu.edu.au> + Small changes by Bram Moolenaar. Edited by Juergen Weigert. + +Manual page for xxd Mar 2026 XXD(1) |