change disk size of VirtualBox, in osX

http://osxdaily.com/2015/04/07/how-to-resize-a-virtualbox-vdi-or-vhd-file-on-mac-os-x/

applejack:MacOS hqin$ VBoxManage modifyhd /Users/hqin/VirtualBox\ VMs/windows10/

Logs/                windows10.vbox       windows10.vbox-prev  windows10.vdi        

applejack:MacOS hqin$ VBoxManage modifyhd --resize 40000 /Users/hqin/VirtualBox\ VMs/windows10/windows10.vdi 

0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

applejack:MacOS hqin$ VBoxManage showhdinfo  /Users/hqin/VirtualBox\ VMs/windows10/windows10.vdi 

UUID:           3a38dc04-987c-46be-9dda-1ded6cece216

Parent UUID:    base

State:          created

Type:           normal (base)

Location:       /Users/hqin/VirtualBox VMs/windows10/windows10.vdi

Storage format: VDI

Format variant: dynamic default

Capacity:       40000 MBytes

Size on disk:   20154 MBytes

Encryption:     disabled

In use by VMs:  windows10 (UUID: 46645298-3095-4fa0-8b95-f625b89c4b24)