Sunday, October 18, 2020

Fedora 32 : About positive and negative lookahead with Bash commands.

Today I will talk about something more complex in Linux commands called: positive and negative lookahead.
This solution can be found in several programming languages including Bash
The lookahead process is part of regular expressions.
The lookahead process looks ahead in the string and sees if it matches the given pattern, but then disregard it and move on.
It is very useful when we want to go through the strings.
The lookahead process can be both positive and negative depending on the purpose.
Negative lookahead is indispensable if you want to match something not followed by something else and looks like this:
The string is the question q is analyzed and if it does not match and is not followed by s returns the result.
The positive lookahead it works the same way only now it is parsed if it corresponds to s.
The positive lookahead looks like this:
Let's look at a simple example of detecting the PAE option for the processor.
We can use this command but we will find a lot of information ...
[root@desk mythcat]# cat /proc/cpuinfo
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 58
model name	: Intel(R) Celeron(R) CPU G1620 @ 2.70GHz
stepping	: 9
In some cases, the resulting information can be taken using pipe and grep but they will be increasingly fragmented.
I will use the same command cpuinfo and we will look for the pae information in the flags.
All CPU flags can be found here.
Let's prove with internal lookahead to find the pae flag.
[root@desk mythcat]# cat /proc/cpuinfo | grep -oP '(?='pae')...' 
This result gives me additional information, namely that there are two cores.
Do you have a question?

Saturday, October 17, 2020

Fedora 32 : Visual Code and C# on Fedora distro.

Today I will show you how to use Visual Code with C#.
sudo rpm --import
sudo sh -c 'echo -e "[code]\nname=Visual Studio Code\nbaseurl=
vscode\nenabled=1\ngpgcheck=1\ngpgkey=" > 
Then use dnf to check and install this editor.
#dnf check-update
#dnf install code
Use Extensions button or Ctrl+Shift+X keys to open in the left side area and intall the C# extension from Microsoft by pressing the Install button, see:

Created a folder named CSharpProjects and using the linux terminal execute the following command:
[mythcat@desk CSharpProjects]$ dotnet new mvc -au None -o aspnetapp
The template "ASP.NET Core Web App (Model-View-Controller)" was created successfully.
This template contains technologies from parties other than Microsoft, 
see for details.

Processing post-creation actions...
Running 'dotnet restore' on aspnetapp/aspnetapp.csproj...
  Restore completed in 112.76 ms for /home/mythcat/CSharpProjects/aspnetapp/aspnetapp.csproj.

Restore succeeded.

[mythcat@desk CSharpProjects]$ cd aspnetapp/
[mythcat@desk aspnetapp]$ code .
This command will open the Visual Code. At this point, in the aspnetapp folder is an ASP.NET project open in Visual Code. You can run this project with command:
[mythcat@desk aspnetapp]$ dotnet run
warn: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[35]
      No XML encryptor configured. Key {4c284989-9a5d-4ea7-89e2-a383828fd7ab} may be persisted 
      to storage in unencrypted form.
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: https://localhost:5001
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://localhost:5000
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
      Content root path: /home/mythcat/CSharpProjects/aspnetapp
You can open the https://localhost:5001/ and see the default Welcome page from ASP.NET.

Saturday, October 3, 2020

Fedora 32 : Create games with Phaser Editor 2D.

Today I install Phaser Editor 2D on Fedora 32, you can download it from the official website. I create an account and I download the archive for Linux. After unarchive I used very simple:
[mythcat@desk ~]$ cd PhaserEditor2D/
[mythcat@desk PhaserEditor2D]$ ls
editor  PhaserEditor2D  README.TXT  templates
[mythcat@desk PhaserEditor2D]$ ./PhaserEditor2D 
Phaser Editor 2D - v3.7.1

=> Running in Free mode (only 70 files per project allowed)
=> Purchase a license:

2020/10/03 16:17:51 Loading workspace at /home/mythcat/PhaserEditor2D_Projects
2020/10/03 16:17:51 Listening at

Play IDE online :
Documentation   :
File bugs/ideas :
Keep in contact :

=> Open the web browser at

2020/10/03 16:17:52 No updates available.
Phaser Editor 2D is a commercial IDE to develop video-games. It is delivered as an offline product and users can run it for free (with certain limitations) or can purchase a license key to unlock all features. Phaser Editor 2D version 3, the latest, is a complete new software based on web technologies. So we created Play Phaser Editor 2D, a small service to allow Phaser Editor 2D license owners, to run the editor and create small projects in the cloud. However, in the future, we will provide a different cloud service with options for storage, collaboration, publishing, integration with other services and payment. These are the Play Phaser Editor 2D available plans: Free Plan and Premium Plan About Free Plan: Running the FREE PLAN 0B/50MB of storage is used 59 days before expiration date The Premium Plan comes with these options:
  • One Year License - 30$ Valid for one year after the purchase. Phaser Editor 2D Team email support. Write to The option to refund in the first month after the purchase.
  • Two Years License - 45$ Valid for two years after the purchase. Phaser Editor 2D Team email support. Write to The option to refund in the first month after the purchase.
  • Lifetime License - 75$ Never expires. Phaser Editor 2D Team email support. Write to The option to refund in the first month after the purchase.
  • Two Years Team License - 125$ 5 developers allowed. Valid for two years. Phaser Editor 2D Team email support. Write to The option to refund in the first month after the purchase.
This is a video tutorial from official youtube channel:

Friday, October 2, 2020

Fedora 32 : Can be better? part 015.

In the evening I can spend my time with Fedora 32.

In the last few days I studied GTK # a bit.

I thought it would be useful for Linux users and those who use the language of the FASM assembler to have an editor.

Tonight I created this simple project this simple project named fasm_editor.

The objectives of this project are:

  • creating a functional editor;
  • implementation of running and compilation requirements;
  • settings specific to the Linux operating system;

I believe that this way Fedora Linux can be improved and become better.