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Identify all amazon cloudformation scripts recursively using ripgrep
This assumes you are in the cwd of where you put your s3 scripts. Its useful if someone decides to create aws cloudformation scripts and doesn't add the 'yaml' or .yml extension.

Get information about memory modules
To take information about the characteristics of the installed memory modules.

Test speaker channels
Useful tool to test if all speaker channels are working properly. speaker-test is part of alsa-utils package

Discover the process start time
That is useful to discover the start time of process older than 1 day. You can also run: $ ls -ld /proc/PID That's returning the creation date of the proc files from the process. Some users reported that this way might show you a wrong date since any other process like cron, for example, could change this date.

Turn On/Off Keyboard LEDs via commandline
Usefull as a light blink to remember events, mails, intrusions, etc... yet another output Since nobody ever uses the scroll lock function... Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick ) xset led 3 turns on the third led, ie, Scroll lock xset -led 3 turns it off xset led 1 turns on Numerical Lock led ( doesn t work on all computer ) xset led 2 turns on Caps Lock led ( idem ) Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)

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

Faster find and move using the find and xargs commands. Almost as fast as locate.
Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

View the current number of free/used inodes in a file system
tune2fs also provides the same information . But the information does not give the current usage , it gives the information when the file system was last mounted. http://www.zaman4linux.in/2010/10/using-up-all-the-free-inodes.html

Take a file as input (two columns data format) and sum values on the 2nd column for all lines that have the same value in 1st column
Example: $ cat

Compress logs older than 7 days


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