How to convert milliseconds into human readable form?

Well, since nobody else has stepped up, I'll write the easy code to do this:

x = ms / 1000
seconds = x % 60
x /= 60
minutes = x % 60
x /= 60
hours = x % 24
x /= 24
days = x

I'm just glad you stopped at days and didn't ask for months. :)

Note that in the above, it is assumed that / represents truncating integer division. If you use this code in a language where / represents floating point division, you will need to manually truncate the results of the division as needed.

Let A be the amount of milliseconds. Then you have:

seconds=(A/1000)%60
minutes=(A/(1000*60))%60
hours=(A/(1000*60*60))%24

and so on (% is the modulus operator).

Hope this helps.