Binary search/replace

xxd < orig | sed 's/A/B/' | sed 's/HEXA/HEXB/' | xxd -r > new
Replaces A with B in binary file "orig" and saves the result to "new". You must have the hex representations of A & B. Try od: echo -e "A\c" | od -An -x

By: wwest4
2009-02-05 20:25:04

1 Alternatives + Submit Alt

What Others Think

By default xxd creates a formatted hex dump, which will cause this command to miss instances where the string wraps to a new line. Use the -p option instead to skip formatting: xxd -p < orig | sed 's/HEXA/HEXB/' | xxd -r -p > new $
unixmonkey6864 · 494 weeks ago
This has a few problems still. Inefficient for large files, doesn't align on byte boundries and xxd -p still has new-lines so wrapped hex won't get matched. You can use Perl's RE to do hex matches for you by using the \x{XX} expression where "XX" is the hex byte code. For example: perl -pe 's/\x{3C}\x{21}/\x{3D}/g;s/\x{2D}/\x{3D}/g' < orig > new This replaces "
edelbrp · 478 weeks and 5 days ago
Oops, the end of my comment got truncated. Anyways, you can look up 0x3C,0x21, etc. to see what chars I'm replacing and with what in my example above.
edelbrp · 478 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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