* "all" target is default
* stdout is always captured, but no target is created if it was empty
* empty targets are considered always out of date
-* .do's $3 is relative path to the file in same directory
+* .do's $3 is relative path to the file in target directory
* .do search goes up to / by default, but can be limited with either
$REDO_TOP_DIR environment variable, or by having .redo/top file in it
* target's completion messages are written after they finish