Add VLC_VAR_GET{MIN,MAX,STEP} commands. Make it possible to use VLC_VAR_INHERITVALUE with a 2nd argument which will be used as the variable name to inherit (for example you want to inherit a variable named "v4l2-hue" into a variable named "hue": vlc_value_t val; val.psz_string = strdup( "v4l2-hue" ); var_Change( p_demux, "hue", VLC_VAR_INHERITVALUE, NULL, &val ); free( val.psz_string ); )