+ Defaults to false.
+
+ "import [ %options ]"
+ In the parent process, "import" calls "analyse" with the arguments it
+ received itself - except that if no "file" option was supplied, it tries
+ to pick the first caller context that looks like a script. When the
+ analyse ends, it exits with the status that was returned.
+
+ In the child process, it just "return"s so that the calling code is
+ actually run under "valgrind".