Commands by eronisko (1)

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escape any command aliases
e.g. if rm is aliased for 'rm -i', you can escape the alias by prepending a backslash: rm [file] # WILL prompt for confirmation per the alias \rm [file] # will NOT prompt for confirmation per the default behavior of the command

watch iptables counters
This will allow you to watch as matches occur in real-time. To filter out only ACCEPT, DROP, LOG..etc, then run the following command: watch 'iptables -nvL | grep -v "0 0" && grep "ACCEPT"' The -v is used to do an inverted filter. ie. NOT "0 0"

Wait for an already launched program to stop before starting a new command.
Referring to the original post, if you are using $! then that means the process is a child of the current shell, so you can just use `wait $!`. If you are trying to wait for a process created outside of the current shell, then the loop on `kill -0 $PID` is good; although, you can't get the exit status of the process.

Take a screenshot every 2 seconds
Take a screenshot every 2 seconds and save it as a png file

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

validate json
I have this saved as jsonlint chmodded +x and file.js is instead $1, but YMMV

Change wallpaper for xfce4 >= 4.6.0
Simply changes the wallpaper of xfce4 from the command line. Not for multiple displays.

Rename files in batch

grep certain file types recursively
-exec works better and faster then using a pipe

Print random emoji in terminal
This will print a random emoji within the range of 1F600 - 1F64F, which includes all the face emoji. Obviously, this will only show something meaningful if your terminal can display emoji, but it may be useful in scripts. This likely requires recent versions of bash


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