How to format partition mac

[André Dias]

Good morning friend,

I created a partition UNIX of inside of the OS X, but exactly thus
when I try to install the FreeBSD I do not obtain, in the other
message I did not place the error, ask for excuses for the
imperfection, rsrs, in the installation of the System, when I arrive
in the part of partition of the disk, the installer says that he does
not have permission to record in the disk and he does not modify the
structure of folders and does not install the FreeBSD. He will be that
plus somebody he had this problem?

Tanks for your attention!
Att. Beren