Is there some command I can use to check to see if there is 2 Gig of space available in a directory before I created a 2 Gig file?
Try the du utility; and do a man du for more specific information about how to use du.
I think that the df utility might be a better choice here. And again there is a man page on this this utility as well.
It is also necessary to have present if:
The filesystem is a large enabled filesystem?
There are a file large limit for users in the server?
Regards, Hugo.