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.
-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 hexdump. This option writes octets as eight digits
-c cols | -cols cols
-c cols | -cols cols format cols ''
-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.
-g bytes | -groupsize bytes
seperate the output of every bytes -g 0 to suppress grouping. Bytes2 in normal 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.
-l len | -len len
stop after writing len
-p | -ps | -postscript | -plain
output in postscript continuous hexdump style. Also known as plain hexdump style.
-r | -revert
reverse operation: convert (or patch) hexdump into binary. If not writing to stdout, xxd writes into its output file without truncating it. Use the combination -r -p to read plain hexadecimal dumps without line number information and without a particular column layout. Additional Whitespace and line-breaks are allowed anywhere.
When used after -r : revert with offset ''
start at seek + indicates that the seek is relative to the current stdin file position (meaningless when not reading from stdin). - indicates that the seek should be that many characters from the end of the input (or if combined with +'' : before the current stdin file position). Without -s option, xxd starts at the current file position.
use upper case hex letters. Default is lower case.
-v | -version
xxd -r has some builtin magic while evaluating line number information. If the ouput file is seekable, then the linenumbers at the start of each hexdump 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 hexdumps, please note that xxd -r skips everything on the input 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 hexdump with xxd -r -p does not depend on the correct number of columns. Here an thing that looks like a pair of hex-digits is interpreted.
Note the difference between % xxd -i file and'' % xxd -i
xxd -s +seek may be different from xxd -s seek , as lseek(2) is used to ''
Rewind stdin before reading; needed because the `cat' has already read to the end of stdin.'' % sh -c 'cat
Hexdump from file position 0x480 (=1024+128) onwards. The `+' sign means % sh -c 'dd of=plain_snippet bs=1k count=1; xxd -s +128
Hexdump from file position 0x100 ( = 1024-768) on.'' % sh -c 'dd of=plain_snippet bs=1k count=1; xxd -s +-768
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 40 octets per line. % xxd -l 120 -ps -c 20 xxd.1 2e544820585844203120224d616e75616c207061 676520666f7220787864220a2e5c220a2e5c2220 32317374204d617920313939360a2e5c22204d61 6e207061676520617574686f723a0a2e5c222020 2020546f6e79204e7567656e74203c746f6e7940 7363746e7567656e2e7070702e67752e6564752e
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 224d .TH XXD 1 000000c: 616e 7561 6c20 7061 6765 2066 anual page f 0000018: 6f72 2078 7864 220a 2e5c 220a or xxd 0000024: 2e5c 2220 3231 7374 204d 6179 . 0000030: 2031 3939 360a 2e5c 2220 4d61 1996.. 000003c: 6e20 7061 6765 2061 7574 686f n page autho 0000048: 723a 0a2e 5c22 2020 2020 546f r:.. 0000054: 6e79 204e 7567 656e 7420 3c74 ny Nugent 0000060: 6f6e 7940 7363 746e 7567 656e ony@sctnugen 000006c: 2e70 7070 2e67 752e 6564 752e .ppp.gu.edu.
Display just the date from the file xxd.1 % xxd -s 0x28 -l 12 -c 12 xxd.1 0000028: 3231 7374 204d 6179 2031 3939 21st May 199
Copy input_file to output_file and prepend 100 bytes of value 0x00.'' % xxd input_file | xxd -r -s 100
Patch the date in the file xxd.1 % echo '0000029: 3574 68' | xxd -r - xxd.1 % xxd -s 0x28 -l 12 -c 12 xxd.1 0000028: 3235 7468 204d 6179 2031 3939 25th May 199
Create a 65537 byte file with all bytes 0x00, except for the last one which is 'A' (hex 0x41).'' % echo '010000: 41' | xxd -r
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
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 between `a' and `z'. :'a,'z!xxd -r
The following error values are returned:
no errors encountered.
operation not supported ( xxd -r -i still impossible).
error while parsing options.
problems with input file.
problems with output file.
(c) 1990-1997 by Juergen Weigert
Distribute freely and credit me, make money and share with me, lose money and don't ask me.