- In build tree In source tree
- This directory just & &,
- Top level &. implies absolute &;
+ Recommended In build tree In source tree
+ when Relative Absolute Relative Absolute
+
+ This directory & &@ &, &@,
+ Top level . &@. &; &@;
+
+Adding `@' means "absolute path". (`&.' is not allowed without @
+because just `&./' is a silly way of writing `.'.) `/' terminates the
+escape (needed if the next thing is not a lowercase character, or
+space). `=' means "just the value, no /". Space starts multi-word
+processing.