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

Analyze awk fields
translate and number lines is simpler and you use tr to choose your delimiter (eg for csv files)

Generate random IP addresses
It never ends

Adjust display hardware brightness [dbus way]

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Display the standard deviation of a column of numbers with awk

Recursively chmod all dirs to 755 and all files to 644

Git fetch all remote branches

archlinux:Delete packages from pacman cache that are older than 7 days
for debian/ubuntu

Count the total amount of hours of your music collection
First the find command finds all files in your current directory (.). This is piped to xargs to be able to run the next shell pipeline in parallel. The xargs -P argument specifies how many processes you want to run in parallel, you can set this higher than your core count as the duration reading is mainly IO bound. The -print0 and -0 arguments of find and xargs respectively are used to easily handle files with spaces or other special characters. A subshell is executed by xargs to have a shell pipeline for each file that is found by find. This pipeline extracts the duration and converts it to a format easily parsed by awk. ffmpeg reads the file and prints a lot of information about it, grep extracts the duration line. cut and sed cut out the time information, and tr converts the last . to a : to make it easier to split by awk. awk is a specialized programming language for use in shell scripts. Here we use it to split the time elements in 4 variables and add them up.


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