C# – First steps with C# and .NET – part 003 .

This tutorial show you how to deal with a C# and forms using Visual Studio Community 2017.
You need to start your project with C# – Windows Form Apps (.NET Framework).
On this default form window project you can change title and some settings like size, colors .
After that , you need to add editbox and label for each area from country , city street and number to window form.
In my example I used text_country for the name of editbox and I let default label1 for the label. The text from label1 I changed to Country to see it on form.
Make this changes for each editbox and label.
You need to have one button named search map point and one webbrowser area to show the location on map.
Next, press on button and make the changes into source code to work with webbrowser area.
The source code is simple – see bellow sorce code and the application screenshot.
The application can be found here:

Go – about errors .

The golang come with a fair amount of functions end up returning errors like values.
The golang errors functions looking like this:

You can use the errors package and that implements functions to manipulate errors.
The official golang example:

You can see how is created the new custom errors using the New function:

The fmt package formats an error value by calling its Errorf() string method, see example:

You can add more information about the error using struct type and fields.
The error type is an interface type and can be used into this way.

And an error variable represents any value that can describe itself as a string, see example:

News: Snort tool version 2.9.11.1 for Windows .

This is a news and a simple fix tutorial about this tool.
The Snort tool version 2.9.11.1 for Windows is easy to install and use it.
You can download it from here.
First you need to create an account to the official website to download the rules and also to use the winpcap tool.
You need make all settings for snort.conf file into etc folder.
Because I used then I fix this:

Don’t worry for some warnings about ERROR: null(0) Failed to parse the IP address:
Then you can use the administrator command shell to run it:

The result of this command is this output:

JavaScript – Processing.js 2D library – part 004.

The Processing.js is available for Linux, Mac OS X, and Windows and come with the last version 3.3.7 (13 March 2018).
Today I tested processing.js for android. They say us about this issue:
Use Processing for Android to create Android apps with ease, including live wallpapers, watch faces, and VR apps. You can run your Processing sketches on Android devices (phones, tablets, watches) with little or no changes in the code, and without worrying about installing SDK files or editing layout files. Processing for Android also lets you accessing the Android API to read sensor data, and exporting your sketch as a signed package ready to upload to the Google Play Store.
To use processing.js for android you need to follow this links:

They tell us about new android processing :
The version 4.0 brings several improvements to the Android mode, incuding new functionality for creating live wallpapers, watch faces, and VR apps.

Linux – ss command .

The TSocket Statistics (ss) command is similar to netstat, and it is used to display useful network socket information.
The ss command syntax come with specify optional flags and filters:

Let’s see some examples with this linux command:

1. List Established Connections
The default run with the ss command display a list of open non-listening sockets that have established connections (for example: TCP, UDP or UNIX sockets)

2. Show Listening Sockets
Than listing all sockets, we can use the -l option to specifically list the sockets that are currently listening for a connection.

3. Show Processes
We can print out the process or PID number that owns a socket with the -p option.

4. Don’t Resolve Service Names
The -n option will not take place and we will instead see the port number rather than the service name.

5. Resolve Numeric Address/Ports
This and resolve both the IP address and port number with the -r option.

6. IPv4 Sockets
We can use the -4 option to only display information corresponding to IPv4 sockets.

7. IPv6 Sockets
We can use the -6 option to only display information related to IPv6 sockets.

8. TCP Only
The -t option can be used to display only TCP sockets and using the -l option print out listening sockets we can see everything listening on TCP.

9. UDP Only
The -u option can be used to display only UDP sockets. As UDP is a connection-less protocol, simply running with only the -u option will display no output. We can instead combine this with the -a or -l option to see all listening UDP sockets, as shown below.

10. Unix Sockets
The -x option can be used to display unix domain sockets only.

11. Show Socket Memory Usage
The -m option can be used to display the amount of memory that each socket is using.

12. Show Internal TCP Information
We can request additional internal TCP information with the -i info option.

13. Show Summary
We can see a quick overview of the statistics with the -s option.

14. Filter Based On State
That specify states including established, syn-sent, syn-recv, fin-wait-1, fin-wait-2, time-wait, closed, closed-wait, last-ack, listen and closing.

15. Show SELinux Context
The -Z and -z options can be used to show the SELinux security context of a socket. In the example below we also use the -t and -l options to only list listening TCP sockets, with the -Z option we can also see the SELinux contexts.

Filtering to list all ports that are less than (lt), greater than (gt), equal to (eq), not equal to (ne), less than or equal to (le), or greater than or equal to (ge).