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Binary search/replace

Terminal - Binary search/replace
xxd < orig | sed 's/A/B/' | sed 's/HEXA/HEXB/' | xxd -r > new
2009-02-05 20:25:04
User: wwest4
Functions: sed
3
Binary search/replace

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

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
xxd -p source | fold -w2 | paste -sd' ' | sed "s/A/B/g" | xxd -p -r > destination
2015-05-26 18:29:48
User: hincor
Functions: fold paste sed
Tags: sed xxd fold paste
2

Replace all instances of "A" with "B" in file "source" saved as file "destination".

!! IF A/B is multi-byte, then separate bytes with spaces like so: "s/20\ 0A/00/g".

Know a better way?

If you can do better, submit your command here.

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 $
Comment by unixmonkey6864 303 weeks and 4 days 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 "

Comment by edelbrp 288 weeks and 1 day 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.

Comment by edelbrp 288 weeks and 1 day ago

Your point of view

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