sysctl hw.modeldiskutil reformat disk0s2
diskutil resizeVolume disk0s2 250g jhfs+ Lion 0b-bash-3.2# diskutil reformat disk0s2
Started erase on disk0s2 Macintosh HD
Unmounting disk
Erasing
Initialized /dev/rdisk0s2 as a 465 GB case-insensitive HFS Plus volume with a 40960k journal
Mounting disk
Finished erase on disk0s2 Macintosh HD
-bash-3.2#-bash-3.2# diskutil resizeVolume disk0s2 250g jhfs+ Lion 0b
Resizing to 250000000000 bytes and adding 1 partition
Started partitioning on disk0s2 Macintosh HD
Verifying the disk
Verifying file system
Volume was successfully unmounted
Performing fsck_hfs -fn -x /dev/rdisk0s2
Checking Journaled HFS Plus volume
Checking extents overflow file
Checking catalog file
Checking multi-linked files
Checking catalog hierarchy
Checking extended attributes file
Checking volume bitmap
Checking volume information
The volume Macintosh HD appears to be OK
File system check exit code is 0
Restoring the original state found as mounted
Resizing
Shrinking file system
Copying booter
Modifying partition map
Initialized /dev/rdisk0s4 as a 232 GB case-insensitive HFS Plus volume with a 24576k journal
Mounting disk
Finished partitioning on disk0s2 Macintosh HD
/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.1 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            250.0 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
   4:                 Apple_Boot Recovery HD             650.0 MB   disk0s5
   5:                  Apple_HFS Lion                    249.1 GB   disk0s4
-bash-3.2#diskutil listLast login: Fri Oct 19 18:02:55 on console
iMac-de-Julien:~ julienberlut$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.1 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            250.0 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
   4:                  Apple_HFS Lion                    248.6 GB   disk0s4
   5:                 Apple_Boot Recovery HD             650.0 MB   disk0s5
iMac-de-Julien:~ julienberlut$diskutil reformat disk0s2
diskutil eraseVolume free null disk0s3
diskutil resizeVolume disk0s2 0bLast login: Fri Oct 19 18:08:37 on ttys000
iMac-de-Julien:~ julienberlut$ diskutil reformat disk0s2
Started erase on disk0s2 Macintosh HD
Unmounting disk
Erasing
Initialized /dev/rdisk0s2 as a 233 GB HFS Plus volume with a 24576k journal
Mounting disk
Finished erase on disk0s2 Macintosh HD
iMac-de-Julien:~ julienberlut$Last login: Fri Oct 19 18:19:59 on ttys001
iMac-de-Julien:~ julienberlut$ diskutil eraseVolume free null disk0s3
Unable to find disk for disk0s3
iMac-de-Julien:~ julienberlut$diskutil listLast login: Fri Oct 19 18:21:20 on ttys000
iMac-de-Julien:~ julienberlut$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.1 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            250.0 GB   disk0s2
   3:                  Apple_HFS Lion                    248.6 GB   disk0s4
   4:                 Apple_Boot Recovery HD             650.0 MB   disk0s5
iMac-de-Julien:~ julienberlut$diskutil resizeVolume disk0s2 0bLast login: Fri Oct 19 18:28:48 on ttys000
iMac-de-Julien:~ julienberlut$ diskutil resizeVolume disk0s2 0b
Started partitioning on disk0s2 Macintosh HD
Verifying the disk
Checking file system
Checking Journaled HFS Plus volume
Checking extents overflow file
Checking catalog file
Checking multi-linked files
Checking catalog hierarchy
Checking extended attributes file
Checking volume bitmap
Checking volume information
The volume Macintosh HD appears to be OK
Resizing
Finished partitioning on disk0s2 Macintosh HD
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.1 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            250.5 GB   disk0s2
   3:                  Apple_HFS Lion                    248.6 GB   disk0s4
   4:                 Apple_Boot Recovery HD             650.0 MB   disk0s5
iMac-de-Julien:~ julienberlut$Last login: Fri Oct 19 18:33:36 on ttys001
iMac-de-Julien:~ julienberlut$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.1 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            250.5 GB   disk0s2
   3:                  Apple_HFS Lion                    248.6 GB   disk0s4
   4:                 Apple_Boot Recovery HD             650.0 MB   disk0s5
iMac-de-Julien:~ julienberlut$ 
	