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I booted a live Ubuntu CD and shrunk my partition down from 400G to about 300G. Right now, I have about 100G of "unallocated." My OS X partition is 47 and I need to increase the space.

I've tried using both Disk Utility on OS X and gparted on Ubuntu, but neither will let me increase the OS X partition space even though I have the 100G unallocated space. When I try to create a new partition from the unallocated space in gparted, I can't select hfs+ as the filesystem (the same type as the OS X partition). If I select unformatted/cleared, I still can't increase the OS X space (Note that the partition creation is not done, just a pending step).

When I try using Disk Utility I get "Mediakit reports partition (map) too small." I don't have a CD for OS X that I can boot from.

Do I need to create a partition from unallocated space first before I can increase the size of the OS X partition? What file system should I select? Are there any other steps I should take in order to increase the OS X partition size?

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