Help for !Choices (Part 8 of the Tutorial)
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!Choices writes a small file of the type specified in the choices window.

Breakdown:
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Because the information about which type the saved file should be is needed in several of the functions in the program, both the handler for the choices window and the selected filetype have been added to the reference block.

Since there is one more menu point, a switch has been added to the menu_choice() function which checks what to do with the selection.  If the selected menu point was "choices", the function choice() is called.  This function opens and displays a window and attaches the necessary handlers.
Icon_SetRadios() marks the top radio button as selected before the window is opened.  This is the default setting for the filetype: A text file.
The event handlers attached to the window check for clicks inside the window and the close button.

If the close button is clicked, the function close_win() is called.  This function deletes the window and sets the window handler back to NULL.  Alternatively (as Save_InitSaveWindowHandler() does) the window could simply be hidden.

If one of the radio buttons is clicked, radio() is called, where Icon_WhichRadio() checks which button was pressed and a switch statement sets the filetype for the save file accordingly.  