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Showing posts from April, 2009

Automated Checksums

I'm creating some checksums today for a folder full of large files. This is the method, which I found on the ubuntu forums. Essentially md5sum is called on each file with 'find -exec' : find -type f -exec md5sum "{}" \; > md5sum.txt ' find ' returns the contents of the directory, ' -type f ' ensures only regular files are returned, I'm not sure what the ' "{}" \;' part is for, finally I added '> md5sum.txt' to send the output to a file. This call can take a very long time depending on the size of files it is being called on, so I checked up on it by counting the lines in md5sum.txt with the following command: cat md5sum.txt | nl | tail -1 | cut -f 1 What this does is list the entire md5sum.txt file, count each line with 'nl' , output only the last line (aka first from the end) with 'tail - 1' then return only the first field of that line with 'cut -f 1' Finally