# SDL_isspace Report if a character is whitespace. ## Header File Defined in [<SDL3/SDL_stdinc.h>](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_stdinc.h) ## Syntax ```c int SDL_isspace(int x); ``` ## Function Parameters | | | | | --- | ----- | ------------------------- | | int | **x** | character value to check. | ## Return Value (int) Returns non-zero if x falls within the character class, zero otherwise. ## Remarks **WARNING**: Regardless of system locale, this will only treat the following ASCII values as true: - space (0x20) - tab (0x09) - newline (0x0A) - vertical tab (0x0B) - form feed (0x0C) - return (0x0D) ## Thread Safety It is safe to call this function from any thread. ## Version This function is available since SDL 3.2.0. ---- [CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategoryStdinc](CategoryStdinc)