The file tk.h should be considered a public declaration of the Tk C functions, defines/macros, and structures which a developer can safely depend on. (Some extensions also use things from tkInt.h, but the price for that is that they require more maintenance in order to keep working. Stick with tk.h as long as possible.)

Tk C functions include:

• Tk_3DBorderColor
• Tk_3DBorderGC
• Tk_3DHorizontalBevel
• Tk_3DVerticalBevel
• Tk_AddOption
• Tk_Alloc3DBorderFromObj
• Tk_AllocBitmapFromObj
• Tk_AllocColorFromObj
• Tk_AllocCursorFromObj
• Tk_AllocFontFromObj
• Tk_AttachHWND
• Tk_Attributes
• Tk_BindEvent
• Tk_CanvasDrawableCoords
• Tk_CanvasEventuallyRedraw
• Tk_CanvasGetCoord
• Tk_CanvasPsBitmap
• Tk_CanvasPsColor
• Tk_CanvasPsFont
• Tk_CanvasPsPath
• Tk_CanvasPsStipple
• Tk_CanvasPsY
• Tk_CanvasSetStippleOrigin
• Tk_CanvasTagsOption
• Tk_CanvasTextInfo
• Tk_CanvasTkwin
• Tk_CanvasWindowCoords
• Tk_ChangeWindowAttributes
• Tk_Changes
• Tk_CharBbox
• Tk_Class
• Tk_ClearSelection
• Tk_ClipboardAppend
• Tk_ClipboardClear
• Tk_CollapseMotionEvents
• Tk_Colormap
• Tk_ComputeTextLayout
• Tk_ConfigureInfo
• Tk_ConfigureValue
• Tk_ConfigureWidget
• Tk_ConfigureWindow
• Tk_CoordsToWindow
• Tk_CreateBinding
• Tk_CreateBindingTable
• Tk_CreateClientMessageHandler
• Tk_CreateErrorHandler
• Tk_CreateEventHandler
• Tk_CreateImageType
• Tk_CreateItemType
• Tk_CreateOptionTable
• Tk_CreatePhotoImageFormat
• Tk_CreateSelHandler
• Tk_CreateWindow
• Tk_CreateWindowFromPath
• Tk_DefineBitmap
• Tk_DefineCursor
• Tk_DeleteAllBindings
• Tk_DeleteBinding
• Tk_DeleteBindingTable
• Tk_DeleteClientMessageHandler
• Tk_DeleteErrorHandler
• Tk_DeleteEventHandler
• Tk_DeleteGenericHandler
• Tk_DeleteImage
• Tk_DeleteOptionTable
• Tk_DeleteSelHandler
• Tk_Depth
• Tk_DestroyWindow
• Tk_Display
• Tk_DisplayName
• Tk_DistanceToTextLayout
• Tk_Draw3DPolygon
• Tk_Draw3DRectangle
• Tk_DrawChars
• Tk_DrawFocusHighlight
• Tk_DrawTextLayout
• Tk_Fill3DPolygon
• Tk_Fill3DRectangle
• Tk_FindPhoto
• Tk_FontId
• Tk_Free3DBorder
• Tk_Free3DBorderFromObj
• Tk_FreeBitmap
• Tk_FreeBitmapFromObj
• Tk_FreeColor
• Tk_FreeColorFromObj
• Tk_FreeColormap
• Tk_FreeConfigOptions
• Tk_FreeCursor
• Tk_FreeCursorFromObj
• Tk_FreeFont
• Tk_FreeFontFromObj
• Tk_FreeGC
• Tk_FreeImage
• Tk_FreeOptions
• Tk_FreePixmap
• Tk_FreeSavedOptions
• Tk_FreeTextLayout
• Tk_FreeXId
• Tk_GeometryRequest
• Tk_Get3DBorder
• Tk_Get3DBorderFromObj
• Tk_GetAllBindings
• Tk_GetAnchor
• Tk_GetAnchorFromObj
• Tk_GetAtomName
• Tk_GetBinding
• Tk_GetBitmap
• Tk_GetBitmapFromObj
• Tk_GetCapStyle
• Tk_GetColor
• Tk_GetColorByValue
• Tk_GetColorFromObj
• Tk_GetColormap
• Tk_GetCursor
• Tk_GetCursorFromData
• Tk_GetCursorFromObj
• Tk_GetDash
• Tk_GetFont
• Tk_GetFontFromObj
• Tk_GetFontMetrics
• Tk_GetGC
• Tk_GetHINSTANCE
• Tk_GetHWND
• Tk_GetImage
• Tk_GetImageMasterData
• Tk_GetItemTypes
• Tk_GetJoinStyle
• Tk_GetJustify
• Tk_GetJustifyFromObj
• Tk_GetMMFromObj
• Tk_GetNumMainWindows
• Tk_GetOption
• Tk_GetOptionInfo
• Tk_GetOptionValue
• Tk_GetPixels
• Tk_GetPixelsFromObj
• Tk_GetPixmap
• Tk_GetRelief
• Tk_GetReliefFromObj
• Tk_GetRootCoords
• Tk_GetScreenMM
• Tk_GetScrollInfo
• Tk_GetScrollInfoObj
• Tk_GetSelection
• Tk_GetUid
• Tk_GetVRootGeometry
• Tk_GetVisual
• Tk_Grab
• Tk_HWNDToWindow
• Tk_HandleEvent
• Tk_Height
• Tk_IdToWindow
• Tk_ImageChanged
• Tk_Init
• Tk_InitImageArgs
• Tk_InitOptions
• Tk_InitStubs
• Tk_InternAtom
• Tk_InternalBorderBottom
• Tk_InternalBorderLeft
• Tk_InternalBorderRight
• Tk_InternalBorderTop
• Tk_IntersectTextLayout
• Tk_IsContainer
• Tk_IsEmbedded
• Tk_IsMapped
• Tk_IsTopLevel
• Tk_Main
• Tk_MainLoop
• Tk_MainWindow
• Tk_MaintainGeometry
• Tk_MakeWindowExist
• Tk_ManageGeometry
• Tk_MapWindow
• Tk_MeasureChars
• Tk_MinReqHeight
• Tk_MinReqWidth
• Tk_MoveResizeWindow
• Tk_MoveToplevelWindow
• Tk_MoveWindow
• Tk_Name
• Tk_NameOf3DBorder
• Tk_NameOfAnchor
• Tk_NameOfBitmap
• Tk_NameOfCapStyle
• Tk_NameOfColor
• Tk_NameOfCursor
• Tk_NameOfFont
• Tk_NameOfImage
• Tk_NameOfJoinStyle
• Tk_NameOfJustify
• Tk_NameOfRelief
• Tk_NameToWindow
• Tk_Offset
• Tk_OwnSelection
• Tk_Parent
• Tk_ParseArgv
• Tk_PathName
• Tk_PhotoBlank
• Tk_PhotoExpand
• Tk_PhotoGetImage
• Tk_PhotoGetSize
• Tk_PhotoPutBlock
• Tk_PhotoPutZoomedBlock
• Tk_PhotoSetSize
• Tk_PointToChar
• Tk_PostscriptFontName
• Tk_QueueWindowEvent
• Tk_RedrawImage
• Tk_ReqHeight
• Tk_ReqWidth
• Tk_ResizeWindow
• Tk_RestackWindow
• Tk_RestoreSavedOptions
• Tk_RestrictEvents
• Tk_SafeInit
• Tk_Screen
• Tk_ScreenNumber
• Tk_SetAppName
• Tk_SetBackgroundFromBorder
• Tk_SetCaretPos
• Tk_SetClass
• Tk_SetClassProcs
• Tk_SetGrid
• Tk_SetInternalBorder
• Tk_SetInternalBorderEx
• Tk_SetMinimumRequestSize
• Tk_SetOptions
• Tk_SetWindowBackground
• Tk_SetWindowBorder
• Tk_SetWindowBorderPixmap
• Tk_SetWindowBorderWidth
• Tk_SetWindowColormap
• Tk_SetWindowVisual
• Tk_SizeOfBitmap
• Tk_SizeOfImage
• Tk_StrictMotif
• Tk_TextLayoutToPostscript
• Tk_TextWidth
• Tk_Uid
• Tk_UndefineCursor
• Tk_UnderlineChars
• Tk_UnderlineTextLayout
• Tk_Ungrab
• Tk_UnmaintainGeometry
• Tk_UnmapWindow
• Tk_UnsetGrid
• Tk_Visual
• Tk_Width
• Tk_WindowId
• Tk_X
• Tk_Y
• Tk_SetWindowBackgroundPixmap
• Tk_CreateGenericHandler
• Tk_SafeInit() forward compatibility

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