iostream: Note that the new name has nothing to do with C++'s iostream class.

docs/README-migration.md

@@ -1157,10 +1157,12 @@ The following symbols have been renamed:
 * RW_SEEK_END => SDL_IO_SEEK_END
 * RW_SEEK_SET => SDL_IO_SEEK_SET
 
-SDL_rwops.h is now named SDL_iostream.h.
+SDL_rwops.h is now named SDL_iostream.h
 
 SDL_RWops is now an opaque structure, and has been renamed to SDL_IOStream. The SDL3 APIs to create an SDL_IOStream (SDL_IOFromFile, etc) are renamed but otherwise still function as they did in SDL2. However, to make a custom SDL_IOStream with app-provided function pointers, call SDL_OpenIO and provide the function pointers through there. To call into an SDL_IOStream's functionality, use the standard APIs (SDL_ReadIO, etc), as the function pointers are internal.
 
+SDL_IOStream is not to be confused with the unrelated standard C++ iostream class!
+
 The RWops function pointers are now in a separate structure called SDL_IOStreamInterface, which is provided to SDL_OpenIO when creating a custom SDL_IOStream implementation. All the functions now take a `void *` userdata argument for their first parameter instead of an SDL_IOStream, since that's now an opaque structure.
 
 SDL_RWread and SDL_RWwrite (and the read and write function pointers) have a different function signature in SDL3, in addition to being renamed.

include/SDL3/SDL_iostream.h

@@ -24,6 +24,9 @@
  *
  *  This file provides a general interface for SDL to read and write
  *  data streams.  It can easily be extended to files, memory, etc.
+ *
+ *  SDL_IOStream is not related to the standard C++ iostream class, other
+ *  than both are abstract interfaces to read/write data.
  */
 
 #ifndef SDL_iostream_h_