-If the command trace flag is set to 1, then commands are
-printed on stderr before they are executed in a format
-which is very similar to the one used by guestfish. In
-other words, you can run a program with this enabled, and
-you will get out a script which you can feed to guestfish
-to perform the same set of actions.
+If the command trace flag is set to 1, then libguestfs
+calls, parameters and return values are traced.