Commands by GouNiNi (3)

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burn an ISO image to writable CD
Does life get much easier? Read up about wodim for an understanding of its origins in relation to the older `cdrecord` utility

Display command lines visible on commandlinefu.com homepage
Uses the fabulous Hpricot library to parse HTML from Ruby. Extracts all elements of "command' class and displays unescaped text from inside these elements. The following command can help install dependencies (apart from Ruby itself) $ gem sources -a http://gems.github.com && sudo gem install why-hpricot

Searches $PATH for files using grep
Best to put it in a file somewhere in your path. (I call the file spath) #!/bin/bash IFS=:; find $PATH | grep $1 Usage: $ spath php

statistics in one line
In this example, file contains five columns where first column is text. Variance is calculated for columns 2 - 5 by using perl module Statistics::Descriptive. There are many more statistical functions available in the module.

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"

clone directory structure
dir1 and all its subdirs and subdirs of subdirs ... but *no files* will be copied to dir2 (not even symbolic links of files will be made). To preserve ownerships & permissions: $ cp -Rps dir1 dir2 Yes, you can do it with $ rsync -a --include '*/' --exclude '*' /path/to/source /path/to/dest too, but I didn't test if this can handle attributes correctly (experiment rsync command yourself with --dry-run switch to avoid harming your file system) You must be in the parent directory of dir1 while executing this command (place dir2 where you will), else soft links of files in dir2 will be made. I couldn't find how to avoid this "limitation" (yet). Playing with recursive unlink command loop maybe? PS. Bash will complain, but the job will be done.

Youtube-dl gone stale on you/stopped working (Ubuntu)?
If you update youtube-dl from the repos, it becomes out-of-date quickly. Luckily, it can auto-update.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

awk using multiple field separators
You can use multiple field separators by separating them with | (=or). This may be helpful when you want to split a string by two separators for example. #echo "one=two three" | awk -F "=| " {'print $1, $3'} one three

Create a new file


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