Commands by billcarroll (1)

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Start screen with name and run command
Runs an instance of screen with name of "name_me" and command of "echo "hi"" To reconnect to screen instance later use: screen -r name_me

extract element of xml
Prints the value of a XML node rather than the entire node.

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Stores the certificate expiration date on the variable A
Stores the certificate expiration date on the variable A

Super Speedy Hexadecimal or Octal Calculations and Conversions to Decimal.
^Hexadecimal Ten minus Octal Ten is Eight(in Decimal). $ echo "$(( 0xaf )) = $(( 0257 ))" ^Hexadecimal AF and Octal 257 are both Decimal 175.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Connect to google talk through ssh by setting your IM client to use the localhost 5432 port
If your firewall or proxy at your location prevents connection to a particular host or port, you can use ssh to tunnel to your home server and do it there instead.

get the ascii number with bash builtin printf

Adjust display hardware brightness [dbus way]

Show a curses based menu selector
Not so much handy by itself, but very nice in shell scripts. This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like: "one" "two" "three" "four" "etc" For those who prefer bash expansion over gratuitious typing: $ whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} ) Things to note: The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time. If the status is 1, it will be selected by default. anything else, will be deselected.


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