Commands by plivox (1)

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Optimal way of deleting huge numbers of files
This command works by rsyncing the target directory (containing the files you want to delete) with an empty directory. The '--delete' switch instructs rsync to remove files that are not present in the source directory. Since there are no files there, all the files will be deleted. I'm not clear on why it's faster than 'find -delete', but it is. Benchmarks here: https://web.archive.org/web/20130929001850/http://linuxnote.net/jianingy/en/linux/a-fast-way-to-remove-huge-number-of-files.html

list files recursively by size

Catch a proccess from a user and strace it.
It sits there in a loop waiting for a proccess from that user to spawn. When it does it will attach strace to it

I hate `echo X | Y`
apart from not being generalisable to all shells, `Y <<< X` seems nicer to me than `echo X | Y`, e.g. $ <<< lol cat; it reads easier, you type less, and it also looks cool

diff current vi buffer edits against original file

Normalize volume output in MPlayer
Works really well for playing DVDs, which have the volume turned way down for some reason. The `2' method is better IMHO because it will adjust to changing loud/soft parts. If you want to add it to your ~/.mplayer/config: # format: volnorm[=method:target] # method: # 1: use single sample (default) # 2: multiple samples # target: # default is 0.25 af-add=volnorm=2:0.75

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)

quickly backup or copy a file with bash

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"

Compute running average for a column of numbers
This is an on-line algorithm for calculating the mean value for numbers in a column. Also known as "running average" or "moving average".


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