.FREEDC allows use of the Windows graphics engine to draw in a PC Logo for Windows window. The required input is the handle for the window which was used as input for a previous .GETDC command. .FREEDC releases any device context previously obtained by the .GETDC command and returns it to Windows. It is essential to release this device context number with the .FREEDC command, since the number of device contexts which Windows can manage is limited. Using .GETDC without a corresponding .FREEDC command may cause Windows to crash.
? MAKE "MY.DC .GETDC .HWND
? .FREEDC .HWND