Commands using echo (1,545)

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Quickest way to sort/display # of occurences

Multi-thread any command
For instance: $ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Save man pages to pdf

Generate a list of installed packages on Debian-based systems
This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use: $ sudo dpkg --set-selections < LIST_FILE

Mount a disk image (dmg) file in Mac OSX
To unmount, replace "attach" with "eject"

Anti DDOS
Takes IP from web logs and pipes to iptables, use grep to white list IPs.. use if a particular file is getting requested by many different addresses. Sure, its already down pipe and you bandwidth may suffer but that isnt the concern. This one liner saved me from all the traffic hitting the server a second time, reconfigure your system so your system will work like blog-post-1.php or the similar so legitimate users can continue working while the botnet kills itself.

Rename files in batch

Output Windows services in a neatly formated list (cygwin)
Outputs Windows Services service name and display name using "sc query", pipes the output to "awk" for processing, then "column" for formatting. List All Services: $ sc query state= all | awk '/SERVICE_NAME/{printf"%s:",$2;getline;gsub(/DISP.*:\ /,"");printf"%s\n",$0}' | column -ts\: List Started Services: $sc query | awk '/SERVICE_NAME/{printf"%s:",$2;getline;gsub(/DISP.*:\ /,"");printf"%s\n",$0}' | column -ts\: List Stopped Services: $sc query state= inactive| awk '/SERVICE_NAME/{printf"%s:",$2;getline;gsub(/DISP.*:\ /,"");printf"%s\n",$0}' | column -ts\:

Show the key code for keyboard events include the Fn keys
The keycodes are a result of pressing: Mute (Fn+F1) a


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