Before explaining the topic mentioned in the title, I will briefly explain what a shell is. In general terms, a shell corresponds in the computer world to a command interpreter where the user has an available interface (CLI, Command-Line Interface), through which he has the possibility of accessing services of the operating system as well as executing or invoking programs. The term of shell comes from the use of consoles under the UNIX operating system in the 70’s, where they were connected to the central computer and started to work there. …

C language (

When we use the gcc in the command line to compile a program in C language, internally several processes are being carried out to take our source code files to binary or executable files.

To understand this more in detail I will carry out a series of steps.

  1. First we will create a main.c file, using the Emacs editor.
emacs main.c

2. We add the following basic code, a typical hello world !.

#include <stdio.h>int main()
printf("Hello World");
return 0;

3. To achieve a simple compilation in GNU / Linux systems, it would be the following:


direct access (

It is usual that people who are initiated in the world of Linux and who worked in Windows, always want to create shortcuts to their archives or folders of daily use.

In linux these shortcuts are known as hard links and symbolic links.

In the case of hard links, in linux the files and folders are assigned an integer number known as inode which in turn is housed in a specific space of the hard disk, which the hard link and the file share the same inode.

To create a hard link you must follow the following steps:

  1. We create…

Command line (

When working with the linux command line, it is very common to use the ls command. This command means list, allowing you to list the file and directories of the working directory or of a specific directory.

For example if we are located on a directory that has several files with different extensions, of which we only need to list those with the extension .c (A .C file can include the complete source code written in C or C ++.), Next command to type the: ls * .c.

As indicated previously, ls will list the files afbetically, the sign * is an indicative that shows all the elements and finally .c refers to the files that end with that extension.

It should be noted that the ls command has several very useful options to view the listed files or directories.

Samuel A. Florez

Web Developer

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