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list files recursively by size

Block an IP address from connecting to a server
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

Cleanup Docker
# Delete all containers docker rm $(docker ps -a -q) # Delete all images docker rmi $(docker images -q)

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

list files recursively by size

Backup a local drive into a file on the remote host via ssh

Analyze awk fields
Breaks down and numbers each line and it's fields. This is really useful when you are going to parse something with awk but aren't sure exactly where to start.

Find the package that installed a command

Create a bunch of dummy text files
Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)

Replace multiple file extensions with a single extension
The above is just a prove of concept based around the nested bash substitution. This could be useful in situations where you're in a directory with many filetypes but you only want to convert a few. $ for f in *.bmp *.jpg *.tga; do convert $f ${f%.*}.png; done or you can use ls | egrep to get more specific... but be warned, files with spaces will cause a ruckus with expansion but the bash for loop uses a space delimited list. $ for f in $(ls | egrep "bmp$|jpg$|tga$"); do convert $f ${f%.*}.png; done I'm guessing some people will still prefer doing it the sed way but I thought the concept of this one was pretty neat. It will help me remember bash substitutions a little better :-P


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