Commands by oracular (4)

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Rotate a pdf by 90 degrees CW

continuously check size of files or directories
very handy if you copy or download a/some file(s) and want to know how big it is at the moment

Convert A USB Cable Into A Smart Home Gadget
An old USB A/B cable is all you need to make your own Smart Home hardware! Cut off and discard the B-portion of the USB cable. On the A side, connect the RED (+) and WHITE (D-) wires via a 1 kiloohm resistor. $Picture: http://imgur.com/dJGVlAU Now plug the cable into a USB port on your Linux computer. Your hardware is ready! Run the above command after changing variable mysms to your personal email-to-SMS gateway info as required by your cellular service provider. The command uses the amazing usbmon tool (see link below) to detect the cable. For the curious, to view the raw usbmon output, run this command: (Also see the sample output) $usbmon -i usb0 How does it work? When the red and white wires are connected (via the 1 kiloohm resistor) the USB hardwere is tricked into thinking that a new USB device is trying to start up. We then use the usbmon utility to capture the host USB events as it tries to talk to the cable. The expect utility watches the usbmon stream and waits for the disconnect text "-2:128" before sending the SMS message. Finally, the sendmail tool is used to email the SMS message to your smartphone via your cellular provider's SMS-to-email gateway. As a result, when the electrical connection between the red and white wire is interrupted, or the USB cable is unplugged from your computer, you get an SMS notification of the disconnect event on your smartphone. Could this be the cheapest smart home gadget ever? What are YOU going to sense with it? Please let me know in the comments and please don't forget to click it up! $ $Links: $ http://www.linuxcertif.com/man/8/usbmon/ http://en.wikipedia.org/wiki/USB#Pinouts http://imgur.com/dJGVlAU

PulseAudio: set the volume via command line
If you have more than one SINK

Group OR'd commands where you expect only one to work
Something to stuff in an alias when you are working in multiple environments. The double-pipe OR will fall through until one of the commands succeeds, and the rest won't be executed. Any STDERR will fall out, but the STDOUT from the correct command will bubble out of the parenthesis to the less command, or some other command you specify.

Delay execution until load average falls under 1.5
If shell escaping of the command is problematic, you can write the command to a file first: $ batch

Kills a process that is locking a file.
Useful when you're trying to unmount a volume and other sticky situations where a rogue process is annoying the hell out of you.

Go up multiple levels of directories quickly and easily.
This is a kind of wrapper around the shell builtin cd that allows a person to quickly go up several directories. Instead of typing: cd ../.. A user can type: cd ... Instead of: cd ../../.. Type: cd .... Add another period and it goes up four levels. Adding more periods will take you up more levels.

rename anime fansubs
renames Anime Episodes to files, that can be parsed by sonarr & co

Save a file you edited in vim without the needed permissions
probably just like 1204, but uses tee as a filter (+ I actually understand how this one works)


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