Commands by sn0w (1)

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tail -f a log file over ssh into growl

Create a PNG screenshot of Rigol Ultravision scopes attached per LAN
Scope should have the Rigol Ultravision Technology otherwise it won't accept the command. ImageMagic is required. Scope sends a 1.1M BMP file and converted to PNG it's only 18-20K

list block devices
Shows all block devices in a tree with descruptions of what they are.

Check your hard drive for bad blocks (destructive)
WARNING!!! ALL DATA WILL BE LOST!!! This command should ONLY be run on drives that are meant to be wiped. Data destruction will result from running this command with the '-w' switch. You may run this command with the '-n' switch in place of '-w' if you want to retain all data on the drive, however, the test won't be as detailed, since the '-n' switch provides a non-destructive read-write mode only, whereas '-w' switch actually writes patterns while scanning for bad blocks.

computes the most frequent used words of a text file
using $ cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30 ("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...

Bitcoin Brainwallet Checksum Calculator
A bitcoin "brainwallet" is a secret passphrase you carry in your brain. The Bitcoin Brainwallet Exponent Calculator is the second of three functions needed to calculate a bitcoin PRIVATE key. Roughly, checksum is the first 8 hex digits of sha256(sha256(0x80+sha256(passphrase))) Note that this is a bash function, which means you have to type its name to invoke it

history autocompletion with arrow keys
This will enable the possibility to navigate in the history of the command you type with the arrow keys, example "na" and the arrow will give all command starting by na in the history.You can add these lines to your .bashrc (without &&) to use that in your default terminal.

Check if a package is installed. If it is, the version number will be shown.
If the first two letters are "ii", then the package is installed. You can also use wildcards. For example, . $ dpkg -l openoffice* . Note that dpkg will usually not report packages which are available but uninstalled. If you want to see both which versions are installed and which versions are available, use this command instead: . $ apt-cache policy python

List all files in current dir and subdirs sorted by size
or $ tree -ifsF --noreport .|sort -n -k2|grep -v '/$' (rows presenting directory names become hidden)

List top 10 files in filesystem or mount point bigger than 200MB
Specify the size in bytes using the 'c' option for the -size flag. The + sign reads as "bigger than". Then execute du on the list; sort in reverse mode and show the first 10 occurrences.


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