Commands by billcarroll (1)

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Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

How to get an absolute value
Whenever we are only interested in difference between two numbers and not the positive/negative values we can use this in script.

SSH to a machine's internet address if it is not present on your local network
Ping machine once, waiting 1 second for response until failing. Upon fail, ssh globally, otherwise ssh locally.

Find the package that installed a command

Assign top-level JSON entries to shell variables
A recursive version might be useful too. /dev/tty is used to show which shell variables just got defined.

Find files with lines that do not match a pattern
This one would be much faster, as it's only one executed command.

Big (four-byte) $RANDOM
Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

Record active input of soundcard to file.wav
You'll need sox package in Debian/Ubuntu.

Extended man command
This microscript looks up a man page for each word possible, and if the correct page is not found, uses w3m and Google's "I'm feeling lucky" to output a first possible result. This script was made as a result of an idea on a popular Linux forum, where users often send other people to RTFM by saying something like "man backup" or "man ubuntu one". To make this script replace the usual man command, save it as ".man.sh" in your home folder and add the following string to the end of your .bashrc file: alias man='~/.man.sh'

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