UC3M

The command terminal is one of the applications that we will use when working in Linux. The following figure shows the window and the most important parts.

Figure 13.1.  Command terminal

This figure shows in fact the execution of two programs. The first is konsole and is in charge of opening a window in the desktop like the one shown in the figure. Inside this window there a second program executing, the command interpreter (or “shell”) bash. Both programs coexist, but each element shown in the figure corresponds to one of them. The command interpreter bash is a program that waits until we introduce new-line terminated command, and executes it. Upon termination, it waits for the next command. The text “$” shown when the interpreter is waiting for the next command is called the “prompt”. The messages produced by the executed commands are shown in the screen. The scroll bar in the right side of the window is managed by the konsole program and allows to access messages produced by previous commands that are not visible in the screen. Thus, konsole stores these messages up to a certain number of lines. The options that appear in the upper part of the window are also offered by konsole to configure its behavior.

In the inside part of the window we can see a BASH command. The first symbol is the prompt followed by a command. In this case the command has not produced any message, and upon termination the prompt is shown again. We will use this interpreter in most of the exercises in this course. Thus, in the following section the main commands of this interpreter are explained.

En el siguiente video puedes ver una breve demostración de cómo manejar el intérprete de comandos.