Commands by tlemerond (1)

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Remove today's installed packages

Explanation of system and MySQL error codes
perror should be installed if mysql-server package is installed

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

nice disk usage, sorted by size, see description for full command
full command below, would not let me put full command in text box du -sk ./* | sort -nr | awk 'BEGIN{ pref[1]="K"; pref[2]="M"; pref[3]="G";} { total = total + $1; x = $1; y = 1; while( x > 1024 ) { x = (x + 1023)/1024; y++; } printf("%g%s\t%s\n",int(x*10)/10,pref[y],$2); } END { y = 1; while( total > 1024 ) { total = (total + 1023)/1024; y++; } printf("Total: %g%s\n",int(total*10)/10,pref[y]); }'

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

skip broken piece of a loop but not exit the loop entirely
useful for loops like for i in $(cat list_of_servers); do ssh -q $i hostname; done if there is an unreachable server, you can just press ctrl + \ to skip that server and continue on with the loop

Save history without logout
You can use commands that executed on first console from new opened second console. Sometimes it be very useful :)

Force the script to be started as root
Will run the script as root and exit if the wrong or no password is given. Also will keep the parameters active if any where given.

shuffle lines via perl
Same, without modules... Probably smarter option: just use the shuf command or even sort -R.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Stay in the loop…

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