what's the difference?

[chum]

what's the difference vbet..

1. I haven't seen him in 6 months...

2. I haven't seen him for 6 months..

[John mcneill]

nothing

[Casiopea]

Chum, there is a slight difference:

in 6 months <within the span of that period>
for 6 months <over the span of that period>

[chum]

Can i see it this way?
1. i see the person now...maybe i can use sentence number 1.

2. until now, i haven't seen that person...

[Casiopea]

That works quite well, chum. I never thought of it that way. Thanks.