###### (This is the legacy documentation for stable SDL2, the current stable version; [SDL3](https://wiki.libsdl.org/SDL3/) is the current development version.) # SDL_hid_send_feature_report Send a Feature report to the device. ## Header File Defined in [SDL_hidapi.h](https://github.com/libsdl-org/SDL/blob/SDL2/include/SDL_hidapi.h) ## Syntax ```c int SDL_hid_send_feature_report(SDL_hid_device *dev, const unsigned char *data, size_t length); ``` ## Function Parameters | | | | | ---------------------------------- | ---------- | --------------------------------------------------------------------- | | [SDL_hid_device](SDL_hid_device) * | **dev** | A device handle returned from [SDL_hid_open](SDL_hid_open)(). | | const unsigned char * | **data** | The data to send, including the report number as the first byte. | | size_t | **length** | The length in bytes of the data to send, including the report number. | ## Return Value (int) Returns the actual number of bytes written and -1 on error. ## Remarks Feature reports are sent over the Control endpoint as a Set_Report transfer. The first byte of `data` must contain the Report ID. For devices which only support a single report, this must be set to 0x0. The remaining bytes contain the report data. Since the Report ID is mandatory, calls to [SDL_hid_send_feature_report](SDL_hid_send_feature_report)() will always contain one more byte than the report contains. For example, if a hid report is 16 bytes long, 17 bytes must be passed to [SDL_hid_send_feature_report](SDL_hid_send_feature_report)(): the Report ID (or 0x0, for devices which do not use numbered reports), followed by the report data (16 bytes). In this example, the length passed in would be 17. ## Version This function is available since SDL 2.0.18. ---- [CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategoryHIDAPI](CategoryHIDAPI)