Advantages of command driven interface

Answer 1

A CLI interface can be implemented on far fewer resources. The CLI is far better for scripting and automated purposes, as well as issuing simple commands. Finally, a CLI interface is generally not subject to copyright, whereas GUIs are.

Answer 2

All interfaces are command-driven interfaces. The only difference is in how the commands are generated, whether by clicking or touching a menu option in a GUI (graphical user interface), pushing a real-world button or switch, or by entering the command directly.

Command-line interfaces are extremely powerful interfaces which allow complete control over the underlying device. Unrestricted access to the command-line interface is usually limited to authorised personnel only, such as system administrators and supervisors, while normal users will generally have access to a limited set of commands with limited functionality, often accessible via an user-friendly GUI that acts as a "wrapper" for the underlying command interface.

The majority of GUI applications have command-line interfaces that allow users to modify a program's behaviour by supplying additional parameters to the program before it loads. Generally user's will not enter these commands directly, but will indirectly call them through the operating system's GUI. For instance, double-clicking a document will generate and execute a command line Behind the Scenes which loads the program associated with that type of file and instructs it to open the file you clicked. Similarly if you right-click a file and select print; the operating system generates the appropriate print command for the associated program which then performs the print request (often as a background process without physically presenting itself to the user).

However, the programs themselves may include other options that are not accessible via the operating system's GUI and that may not even be available within its own GUI. To access these features you must use the command prompt and enter the commands directly.

Some command-line interfaces neither have nor require a GUI. For instance, the standard DOS commands, such as COPY and ERASE have no GUI. Thus these commands operate much quicker than the equivalent GUI methods that employ drag-and-drop. But the GUI methods are not merely wrappers for the DOS commands, they are separate commands altogether. They both make the exact same system calls, but the GUI methods include additional code that interacts with the operating system's GUI, such as presenting an animation and playing a sound when you drop a file onto the recycle bin. The equivalent ERASE command simply deletes the file and prints a message at the command prompt to let you know if the file was deleted successfully or to let you know why the file could not be deleted.

Although most programs provide their own GUI, command-line programs are still popular with enthusiasts because of their raw power and speed of execution. However, they are not particularly user-friendly so often the programmer (usually a third-party programmer), will provide a GUI wrapper for the command-line program to make it easier for everyone to make use of the program. In this case the GUI wrapper is simply generating the appropriate command lines according to the options selected by the user using the GUI. The GUI generally does not interact with the command-line program, it simply executes it on the user's behalf. GUI wrappers can often be identified by the fact a command window pops up in the background and disappears when the command has finished its task.

Answer 3

A command driven interface functions as a user's interface to the operating system of a computer. The user types in a command and then receives a response from the system.