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Quick Guide to Using xxd
This article was auto-translated from Chinese. Some nuances may be lost in translation.
xxd is a Linux tool for viewing binary files.
Why Would You Want to Inspect Binary Files?
- To check if the compiled program matches what you expected
- To inspect the contents of image or video files
- Pure curiosity
Using xxd
xxd filename
This outputs the file contents like this:
00000000: 4500 6d00 7000 7400 7900 0000 0000 0000 E.m.p.t.y.......
00000010: 0000 0000 0000 0000 0000 0000 0000 0000 ................It can be divided into three sections: the first is the address of the hex dump (dumping 16 bytes per line by default); the second is the file contents; and the rightmost is the raw representation of the file, where non-printable characters are printed as ..
xxd -r filename
This command can reverse the hex dump back into the original binary file.
Useful Combos
xxd filename | vim -: View a binary file usingvimvim filenameand then run:%!xxd -rinside it to edit binary files using vimxxd filename > dump.hex: Well… dump it directly to a file, which can then be used withdiff
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