text: Make a stream frame available to its consumers
  #include <screen/screen.h>
  int screen_post_stream(screen_stream_t stream, screen_buffer_t buf, int count, const int *dirty_rects, int flags)
  Function Type: Apply Execution
  In addition to the area(s) defined by dirty_rects, consumers may use all the pixels in the buffer. Consumers may also retrieve data from the buffer at times other than when screen_post_stream() is called.
  The function may cause the SCREEN_PROPERTY_RENDER_BUFFERS of the stream to change. Avoid having other threads in the application read this property while one thread is running screen_post_stream() on the same stream. If this happens, the property may reflect out-of-date information that can lead to artifacts.
  0 if the area of the rendering buffer that is marked dirty has been updated and a new set of rendering buffers was returned, or -1 if an error occurred (errno is set; refer to errno.h for more details).