iffit1.i and iffit2.b98 are a test of the C-INTERCAL/cfunge external
calls system. To use the test, use this command:

ick -ea iffit1.i iffit2.b98

What follows is the expected output, annotated to show what causes
each line to be printed.

Before IFFI... Printed by the Funge program before IFFI is loaded.
0              Printed immediately after IFFI loads; the program then
               yields immediately, running the INTERCAL program.
I	       Printed at the start of the INTERCAL program; tests Y.
2	       Printed by the Funge program after (100) is NEXTed to.
	       This tests NEXTING to an L in the Funge program.
III	       Printed by INTERCAL after the Funge program does 2R
	       (i.e. RESUME 2).
IV	       Tests COMING FROM an L when in mark-mode after a NEXT.
5	       Tests NEXTING FROM the INTERCAL program to the Funge
	       program using X.
VI	       Tests RESUMING to the INTERCAL program after the NEXT
	       FROM in the Befunge program.
VII	       Tests that COME FROMs happen at the end of a command.
8	       Tests COMING FROM the INTERCAL program to the Funge
	       program using C.
IX	       Tests FORGET using F, and also RESUME after a COME FROM
	       in the Befunge program.
X	       This (irrelevantly) tests ONCE in the INTERCAL program.
11	       This (likewise irrelevantly) tests that p in Funge has
	       correctly altered the flow of control.
XII	       Tests COMING FROM an L when not in mark-mode.
13	       Tests variable access using G in the Funge program to
	       read an INTERCAL variable, also a second marker.
XIV	       Tests the use of S to set an INTERCAL variable.
15	       Tests that CREATEd commands send values correctly.
16	       Tests that CREATEd commands send bitwidths correctly.
17	       Tests that CREATEd commands send names correctly.
	       The above three tests test CREATION using A and D.
XVIII	       Tests that V sets arguments to CREATED commands
	       correctly, and also that Y correctly reflects the
	       second time.

At this point the program should end, having tested all the commands
in the IFFI fingerprint. (Obviously, this is not an exhaustive test,
because, for instance, G was only used to get onespot variables not
twospot variables.)

It is an interesting challenge to try to figure out how the tests
work, especially given that the Funge program is self-modifying, the
statements in the INTERCAL program don't always do the same thing
every time they're run, and the Funge program modifies the syntax of
the INTERCAL program at runtime.