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Here Strings / A variant of here documents, the format is:
(from bash manpage)
Why remember? Generate!
Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum)
Command makes use of the Malware Hash Registry (http://www.team-cymru.org/Services/MHR/).
It parses the current directory and subdirectories and calculates the md5 hash of the files, then prints the name and sends the hash to the MHR for a lookup in their database.
The 3rd value in the result is the detection percentage across a mix of AV packages.
I liked vaporub's suggestion, here a little simplification of the sed command.
extracts path to each md5 checksum file, then, for each path, cd to it, check the md5sum, then cd - to toggle back to the starting directory. greps at the end to remove cd chattering on about the current directory.
Same result with simpler regular expression..
Generates the md5 hash, without the trailing " -" and with the output "broken" into pairs of hexs.
Nothing special about hashing here, only the use of cut, I think, could result at fewer keystrokes.
Backups $DIR_TO_BACKUP into tape, creating on the fly a MD5SUM file of the backup.
Then rewinds one record on tape and checks if it's well written.
I had the problem that the Md5 Sum of a file changed after copying it to my external disk.
This unhandy command helped me to fix the problem.
This is a beginning script. You can create a file with > filename. You can also use diff to compare output run at different times to verify no change in your files. I apologize in advance if this is too simple. For some it should be a start.
Improvement of the command "Find Duplicate Files (based on size first, then MD5 hash)" when searching for duplicate files in a directory containing a subversion working copy. This way the (multiple dupicates) in the meta-information directories are ignored.
Can easily be adopted for other VCS as well. For CVS i.e. change ".svn" into ".csv":
find -type d -name ".csv" -prune -o -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type d -name ".csv" -prune -o -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
A bit shorter and parallelized. Depending on the speed of your cpu and your disk this may run faster.
Parallel is from https://savannah.nongnu.org/projects/parallel/
All valid files are withheld so only failures show up. No output, all checks good.
usage: sitepass MaStErPaSsWoRd example.com
description: An admittedly excessive amount of hashing, but this will give you a pretty secure password, It also eliminates repeated characters and deletes itself from your command history.
tr '!-~' 'P-~!-O' # this bit is rot47, kinda like rot13 but more nerdy
rev # this avoids the first few bytes of gzip payload, and the magic bytes.