How to use the command 'xprop' (with examples)

The xprop command is a powerful utility in the X Window System used to display and manipulate window properties. It allows users to retrieve detailed information about the properties of windows and fonts in an X server environment. This tool is invaluable for developers, system administrators, and anyone interested in the inner workings of graphical user interfaces within the X Window System. Understanding how to leverage xprop can enhance troubleshooting and performance tuning efforts by revealing the underlying attributes of window elements.

Display the name of the root window

Code:

xprop -root WM_NAME

Motivation:

Determining the name of the root window can be particularly useful for troubleshooting and customizing the desktop environment. The root window is the base of the window hierarchy in an X server, and it often carries critical information regarding the current window manager and its configuration. Knowing the root window’s name can help users identify which desktop environment or window manager is currently active, facilitating adjustments and ensuring compatibility with software requirements.

Explanation:

• xprop: Invokes the xprop command-line utility.
• -root: This option specifies that the command should apply to the root window, which is the top-level window on the display.
• WM_NAME: This property is used to display the name of the window manager, which typically includes the name of the desktop environment or the current session running on the root window.

Example Output:

WM_NAME(STRING) = "KDE Plasma"

This output indicates that the current desktop environment is KDE Plasma, which could inform further configuration or customization steps.

Display the window manager hints for a window

Code:

xprop -name "window_name" WM_HINTS

Motivation:

Accessing window manager hints for a specific window provides key insights into its behavior and interaction with the system. These hints can involve visibility status, input preferences like focus behavior, and window grouping information, all of which can affect how a window is managed by the window manager. Analyzing the WM_HINTS can guide developers, especially those programming or debugging GUI applications, in understanding how their applications will behave or be perceived by different window managers.

Explanation:

• xprop: Initiates the xprop utility.
• -name "window_name": Specifies the exact name of the window for which to retrieve properties. The name should be enclosed in quotes if it contains spaces.
• WM_HINTS: Requests the specific hints related to the window’s management by the window manager, including status and behavior attributes.

Example Output:

WM_HINTS(WM_HINTS):
    Client accepts input or input focus: True
    Initial state is Normal State.

This output reveals that the window is designed to accept user input and that its default state when opening is normal, not minimized or maximized.

Display the point size of a font

Code:

xprop -font "font_name" POINT_SIZE

Motivation:

Knowing the point size of a font can be crucial for graphic designers and developers who aim to create a consistent and visually appealing user interface. Fonts often constitute an important part of application aesthetics and usability, and understanding their properties can help in maintaining uniformity across various components of the graphical interface. This is particularly relevant in applications designed to support multiple languages or custom text-rendering requirements.

Explanation:

• xprop: Calls the xprop utility tool.
• -font "font_name": Specifies the name of the font whose properties are to be displayed. The name should be enclosed in quotes if it includes spaces.
• POINT_SIZE: A property that indicates the size of the font in points, which is crucial for ensuring text appears as intended across various resolutions.

Example Output:

POINT_SIZE(PIXMAP): 12

This output demonstrates that the specified font’s point size is 12, guiding further design decisions in document formatting or application layouts.

Display all the properties of the window with the ID 0x200007

Code:

xprop -id 0x200007

Motivation:

When diagnosing issues within a specific application or window, it can be beneficial to procure all properties associated with that window. By displaying all attributes linked to a window using its unique identifier (ID), developers and system administrators can gain comprehensive insights into the window’s state, permissions, and interactions with the window manager. This information is particularly advantageous when debugging complex window interactions or inconsistencies in appearance and behavior.

Explanation:

• xprop: Executes the xprop command.
• -id 0x200007: Specifies the ID of the window whose properties need to be fetched. Window IDs are hexadecimal numbers that uniquely identify windows in the X server.

Example Output:

_NET_WM_ICON(CARDINAL) = 128, 128, ...
_NET_WM_STATE(ATOM) = 
WM_TRANSIENT_FOR(WINDOW): window id # 0x200005
WM_CLASS(STRING) = "exampleApp", "ExampleApp"

This output provides a detailed list of diverse properties relating to the specified window, including icon specifications, state, and application classification.

Conclusion:

The xprop command is an essential utility for interacting with window properties in an X server environment. Through various scenarios, users can extract critical attributes pertaining to windows and fonts, aiding in tasks ranging from system diagnostics to interface design. By learning to utilize xprop, users can elevate their command-line proficiency and maximize their grasp of window management within the X Window System.