Commands by falcald (1)

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Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by the excellent EVACopy http://evacopy.sourceforge.net

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

recursive search and replace old with new string, inside files
xargs deals badly with special characters (such as space, ' and "). To see the problem try this: touch important_file touch 'not important_file' ls not* | xargs rm Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.

start a tunnel from some machine's port 80 to your local post 2001
now you can acces the website by going to http://localhost:2001/

Down for everyone or just me?
Check if a site is down with downforeveryoneorjustme.com

drop first column of output by piping to this

Check if a string is into a variable
Returns true (0) if the string is into $var, or false (1) if not.

Enable verbose boot in Mac OS X Open Firmware

List just the executable files (or directories) in current directory
Does an 'ls' on just the files and directories in the current directory with an execute bit turned on. This version will list directories. Just tack on "-type f" to the start of the find to omit listing directories and list only files.


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