

Introduction
Magnifying Glass is an application that adds an icon to the system tray. The Magnification is activated by clicking on this icon. When the program is run, it shows a magnifying glass in any place on the screen when left mouse button is pressed.
Topics covered in this program:
- Using mutex in single-instance application.
- Writing application that adds icon to system tray.
- Using invisible
TOPMOST
window to capture mouse input on the whole screen.
- Using message crackers from WindowsX.h.
- Windows graphics (GDI).
Acknowledgements:
History
26 Dec 2001:
- Redrawing problem in Windows 95, 98, reported by PJ Arends.
- Compilation problem when SDK is not installed.
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