SDL_wcslcat - Concatenate wide strings.

       This function is available since SDL 3.2.0.

       This  function appends up to maxlen - SDL_wcslen(dst) - 1 wide characters from src to the end of the wide
       string in dst, then appends a null terminator.

       src and dst must not overlap.

       If maxlen - SDL_wcslen(dst) - 1 is less than or equal to 0, then dst is unmodified.

dst    The destination buffer already containing the first null-terminated wide string. Must not be  NULL
              and must not overlap with src.

       src    The second null-terminated wide string. Must not be NULL, and must not overlap with dst.

       maxlen The length (in wide characters) of the destination buffer.

       SDL_wcslcat - Concatenate wide strings.

       Returns  the  length  (in  wide  characters, excluding the null terminator) of the string in dst plus the
       length of src.

SDL_wcslcpy(3)

Simple Directmedia Layer                           SDL 3.2.20                                     SDL_wcslcat(3)

#include<SDL3/SDL_stdinc.h>size_tSDL_wcslcat(wchar_t*dst,constwchar_t*src,size_tmaxlen);

       It is safe to call this function from any thread.