How to Use the Command 'backlight_control' (with examples)

The backlight_control command is a handy tool for users who need to manage the brightness of their Linux machine’s display effectively. Leveraging percentage values, this command allows users to increase or decrease their screen’s backlight and set it to a specific level, enhancing comfort and visibility. It is particularly useful for both regular users adjusting their screens based on lighting conditions and power users looking to programmatically control screen brightness through scripts.

Use Case 1: Increase/Decrease the Backlight by a Specific Percent Count

Code:

backlight_control +5

or

backlight_control -5

Motivation:

In scenarios where ambient lighting conditions change—such as moving from a bright outdoor environment to a dimly lit room—adjusting your screen’s brightness by small increments can enhance the viewing experience and reduce eye strain. This feature can be especially beneficial for laptop users who frequently move around different environments and need quick adjustments to their screen brightness.

Explanation:

• backlight_control: This is the command used to control the screen’s backlight.
• +5: This argument increases the current backlight brightness by 5 percent.
• -5: Conversely, this option decreases the brightness by 5 percent.

These incremental adjustments provide a versatile way to fine-tune brightness based on personal preference or environmental needs.

Example Output:

Backlight increased by 5%; current level is 45%

or

Backlight decreased by 5%; current level is 35%

Here, the output shows the result of adjusting the backlight, presenting the current brightness level after the change.

Use Case 2: Set the Backlight Strength to a Specific Percent Count

Code:

backlight_control 90

Motivation:

Sometimes, users might prefer setting their backlight to a precise value, especially if they know that a particular brightness level is optimal for their work or leisure activities. For example, during late-night work sessions, setting the brightness to a specific lower percentage like 20 or 30 can be crucial to avoid straining your eyes.

Explanation:

• backlight_control: As with the previous example, this is the command responsible for adjusting the brightness.
• 90: Represents the exact backlight level that the user desires, expressed as a percentage. In this example, 90 percent is chosen, indicating a very bright screen.

This usage ensures that the user can achieve the right comfort level with one simple command without toggling through incremental adjustments.

Example Output:

Backlight set to 90%

The output confirms that the backlight has been set to the exact specified percentage, providing assurance and precision in adjustment.

Use Case 3: Display Help

Code:

backlight_control

Motivation:

When using a command for the first time or when needing to refresh your memory about its features and options, accessing the help menu is incredibly useful. This feature allows users to understand how to employ the command effectively without external resources or guessing.

Explanation:

• backlight_control: Invoked without additional arguments, the command defaults to showing available options and usage instructions. It acts as a guide for users, outlining how to employ the command’s functionalities.

Example Output:

Usage: backlight_control [OPTIONS] PERCENTAGE
  +|-<percentage> : Increase or decrease the brightness by the specified percentage
  <percentage>    : Set brightness to the specified percentage
  help            : Display this help text

The example output provides a concise overview of the command’s usage and options, illustrating the various ways users can interact with the backlight settings.

Conclusion

The backlight_control command provides an intuitive way to manage the screen brightness on a Linux machine, whether by adjusting incrementally or setting precise levels. With the ability to adjust based on immediate needs and environments, users can maintain optimal viewing conditions and conserve energy, all while easily accessible help provides additional support when needed.