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Quickly add a new user to all groups the default user is in
This is a standard procedure for me, whenever I set up a new Raspberry Pi system. Because the default user is "pi", I quickly replace it with my own (e.g. "kostis"), but I have to substitute that user to all of pi's groups first, before deleting the default account. xargs helps a lot with that in a single line, while avoiding boring "for" loops. For everything trickier, there's always "parallel" :)

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

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

Don't spam root. Log your cronjob output to syslog
This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to root@localhost (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

Get a docker container's run command line
A good way to build a new container when you don't remember how you did it the first time

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Find Out My Linux Distribution Name and Version
Another way of do it in debian like distros, don't know if works for others

convert a line to a space

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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