Understanding file permissions and ownership on Linux

The files on a Linux system can have reading permissions, writing permissions, executing (running) permissions or no permissions for the user that owns that files, groups of users or the rest – users who does not own that files and they are not members of any group.

Take screenshot from command line

Take a screenshot of your desktop using the SCROT utility. Basic usage is to call the scrot command in a console, but this would take an instant screenshot of the desktop in the current directory. Thus it would be better used along with the “-d” (delay) option in order to have a time buffer to place the desired objects on the desktop.

Fix NetBeans big fonts on Ubuntu

There is a rather annoying issue related with NetBeans displaying large fonts on Ubuntu for menus and panels. There are some suggestions on Ubuntu forums related with java fonts settings, but there are a couple of better solutions which may improve the way NetBeans looks on Ubuntu when it comes to font size.

Extract audio from video file

Since there are so many tools (Minitube, youtube-dl) which allows you to download video files from YouTube or other video sharing sites, let’s go one step further and extract the sound from the downloaded video file to a mp3 file. The FFmpeg tool will do the trick just fine

CLI search and replace in multiple files

Here is a quick tip about how to find and replace a text in multiple files, from CLI.In this example you have some text files (.txt) with urls like “http://example.com, http://another-example.com…”. What you are trying to do is to replace all “http” references with “https”.