npm

xprop

Display properties of X windows and atoms

brewmacoslinux
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Source

About

Property displayer for X

Commands

xprop

Examples

Interactively select a window and display all its properties$ xprop
Get specific properties of a window by ID$ xprop -id 0x4a00001 WM_NAME WM_CLASS
Select a window by clicking and show only the window name$ xprop WM_NAME