tricky, but not very enjoyable

Nice!

(c-version)

there is a typo in the provided test: The output message labels both expected strings as "S2" - should be labeled as "S1" and "S2".

You're not doing it in-place.

what is this error:
expected [ '7', '6', '5', '4', '3', '2', '1' ] to deeply equal [ 'c', 'b', 'a' ]
my code wotks in browser console though...

nothing, obviously.

Instructions are insufficient and tests don't provide any feedback information.

what should be return from function

This is a very tricky kata. You could have blame the author with such tricky problem, but just do what your mind says then viola it will work!
then you will realize the logic the sensei wants you to know.

clue: the function is void, the length is different and the sensei is clever.

I dont understand , this is my output on my computer:

s1:c b a
s2:7 6 5 4 3 2 1

but tests show:

[Actual]
S1: [1234567]
S2: [abc]
[Expected]
S2: [cba]
S2: [7654321]
[Input]
S1: [1234567]
S2: [abc]

please explain what happens ?

i dont understand what you need me to do after exchanging the values
what should i return with

@Root-Exec. Find another way to exchange the content of the buffers you are given. Don't use **.

As for my OP, that still stands. I think the Kata description should clarifiy the point about strings of different lengths. Meanwhile, tests work OK because even strings of different lengths are within equal sized memory allocations so...

Were you able to figure it out? I changed the tests to use char** for their arguments and that worked all the way up to the "uncheatedly" test which it failed.

You need to modify the contents of existing arrays a and b inside the function, and not assign references to new arrays by these variables (parameters).

Not a kata problem. In fact, I see no problem at all.

Please amplify.