Linux

Did you know that you can replace grep and sed by perl -pe and have the full power of Perl regexs?

Examples:

Imagine you have a file with comma-separated Odoo module names and you want to extract all those that:

1. Are unrelated to payment.
2. Are from any localization except the Spanish one.

Using only grep or sed is very complicated because they don’t support negative lookaheads. However, with Perl it’s “very” easy:

“How to install the application _______?”

I’m sure you’ve asked yourself. If you use GNU/Linux, the usual answer is: by installing a software package.

But… there are many package formats. How do you know which one is best?

Let me tell you.

System packages

I say “system” because, by installing a package in this format, what we are really doing is allowing a new software component to become part of our operating system.

Sometimes you may have a webcam that shows flickering.

How to solve it?

In my case, I have a Logitech C920 HD Pro and I was having this problem.

Why it happens

Usually it is because the camera is working at 60 Hz and the monitor at 50, or vice versa.

How to solve it in Windows

For my particular camera, it was simple:

1. download and install the Camera Settings application.
2. Open it.
3. Set the camera’s refresh rate to match that of the monitor.

How to solve it on Linux

On Linux it is also easy to do if you install the gtk-v4l package. If you are on Fedora 35:

Having a Windows virtual machine in Linux has a lot of utilities:

1. If you’re testing Linux for the first time, it can help you “unhook yourself” from Windows little by little. You know you have Windows there, and that placebo gives you the necessary courage to test this little weird new world that is Linux.
2. You’re a developer and you want to see how your apps or services work on Windows.
3. You need to use one app that has no native Linux alternative and that you cannot run with Wine.
4. You need to use one app that is only available through Windows app store.

It turns out getting it is way easier than what you imagine:

What to do when you find this 💩 in the terminal?

➤ sudo apt-get remove linux-image-generic
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 linux-generic : Depends: linux-image-generic (= 4.4.0.143.151) but it is not going to be installed
 linux-modules-extra-4.4.0-143-generic : Depends: linux-image-4.4.0-143-generic but it is not going to be installed o
                                                  linux-image-unsigned-4.4.0-143-generic but it is not going to be installed
 linux-signed-image-generic : Depends: linux-image-generic but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

It’s a little hard, but let’s go…