How to split large files? (Mac)

You can use the split command via the Terminal:

split -b2000000000 inputfilename

will generate 2GB files with names starting with the letter x and two appended sorted characters, eg: xaa, xab, xac, etc. The original file is left intact.

To put the files back together, type in the Terminal:

cat x* > completefilename

Reference: Mac Forums