Displays the standard AutoCAD color selection dialog box
(acad_colordlg colornum [flag])
Arguments
An integer in the range 0-256 (inclusive), specifying the AutoCAD color number to display as the initial default.
If set to nil, disables the ByLayer and ByBlock buttons. Omitting the flag argument or setting it to a non-nil value enables the ByLayer and ByBlock buttons.
A colornum value of 0 defaults to ByBlock, and a value of 256 defaults to ByLayer.
Return Values
The user-selected color number; otherwise nil, if the user cancels the dialog box.
Examples
Prompt the user to select a color, and default to green if none is selected:
(acad_colordlg 3)
