- RNA support for returning copied strings from functions, flagging strings as PROP_THICK_WRAP does this.

- scene.render_data.frame_path(frame=num), returns the output path for rending images of video.
- scene.render_data.file_extension, readonly attribute, gives the extension ".jpg", ".mov" etc
- player support was guessing names, use the above functions to get the actual names used, accounting for #'s replacing numbers.

source/blender/nodes/intern/CMP_nodes/CMP_outputFile.c

@@ -62,7 +62,7 @@ static void node_composit_exec_output_file(void *data, bNode *node, bNodeStack *
 				}
 			}
 			
-			BKE_makepicstring((Scene *)node->id, string, nif->name, rd->cfra, nif->imtype);
+			BKE_makepicstring(string, nif->name, rd->cfra, nif->imtype, ((Scene *)node->id)->r.scemode & R_EXTENSION);
 			
 			if(0 == BKE_write_ibuf((Scene *)node->id, ibuf, string, nif->imtype, nif->subimtype, nif->imtype==R_OPENEXR?nif->codec:nif->quality))
 				printf("Cannot save Node File Output to %s\n", string);