Here is a list of all struct and union fields with links to the structures/unions they belong to:

### - u -

- SDL_UnloadObject : SDL_DYNAPI_jump_table
- SDL_UnlockAudio : SDL_DYNAPI_jump_table
- SDL_UnlockMutex : SDL_DYNAPI_jump_table
- SDL_UnlockTexture : SDL_DYNAPI_jump_table
- SDL_UpdateWindowSurface : SDL_DYNAPI_jump_table
- SDL_UpdateYUVTexture : SDL_DYNAPI_jump_table
- SDL_UpperBlit : SDL_DYNAPI_jump_table
- ub : __attribute__
- ud : __attribute__
- UINT : ITfCandidateListUIElementVtbl , SDL_VideoData
- uiscreen : SDL_DisplayData
- uiscreenmode : SDL_DisplayModeData
- uiwindow : SDL_WindowData
- ulaw_buf : SDL_PrivateAudioData
- ulaw_only : SDL_PrivateAudioData
- ULONG() : ITfCandidateListUIElementVtbl , ITfDocumentMgrVtbl , ITfInputProcessorProfileActivationSinkVtbl , ITfReadingInformationUIElementVtbl , ITfSourceVtbl , ITfThreadMgrExVtbl , ITfThreadMgrVtbl , ITfUIElementMgrVtbl , ITfUIElementSinkVtbl , ITfUIElementVtbl , SDL_VideoData
- Uninitialize() : sealed
- unknown : SDL_RWops
- UnlockBuffer() : SDL_BWin
- UnlockDevice : SDL_AudioDriverImpl
- UnlockTexture : SDL_Renderer
- unused : DIDEVICEINSTANCE , SDL_Keysym
- uordblks : mallinfo
- UpdateClipRect : SDL_Renderer
- updateFrame : SDL_uikitopenglview
- UpdateTexture : SDL_Renderer
- UpdateTextureYUV : SDL_Renderer
- UpdateViewport : SDL_Renderer
- UpdateWindowFramebuffer : SDL_VideoDevice
- upleft : SDL_QuadTreeChildren
- upright : SDL_QuadTreeChildren
- upsample : SDL_AudioRateFilters
- uq : __attribute__
- uReadingBufLen : SDL_VideoData
- usage : recDevice , recElement
- usagePage : recDevice , recElement
- use_linux_input : DFB_DeviceData
- use_mitshm : SDL_WindowData
- use_streamer : SDL_AudioDevice
- use_vidmode : SDL_DisplayData
- use_xinerama : SDL_DisplayData
- use_xrandr : SDL_DisplayData
- use_yuv_direct : DFB_DeviceData
- use_yuv_underlays : DFB_DeviceData
- used : recDevice::axis_correct
- user : SDL_Event
- userdata : SDL_AudioSpec , SDL_EventWatcher , SDL_HintWatch , SDL_Surface
- userDLL : SDL_VideoData
- userid : haptic_hwdata , recDevice , SDL_hapticlist_item
- userx : SDL_WindowShaper
- usery : SDL_WindowShaper
- uses_gles : SDL_WindowData
- usmblks : mallinfo
- UTF8_STRING : SDL_VideoData
- uw : __attribute__