OS X installer, "Are you sure you want to install on /dev/rdisk2"


Thank you so much for this wonderful software.
I think that it would be great if this message, “Are you sure you want to install on /dev/rdisk2” was changed to something that normal people can comprehend. I had to issue the “mount” command in the terminal to confirm that it was indeed my SD card that was being formatted.

Perhaps it could also show the drive name and the size of the disk? This will make sure that people don’t accidentally nuke “Macintosh HD”. (As a matter of fact, why is this even an option on the list?)

Regards :slight_smile: Also, happy birthday Sam.

My understanding is we do show the disk size and label in the selection dialogue. The confirmation popup just asks you to confirm your choice.

I’ll see what I can do about hiding the hard disk. I think this means we should always hide rdisk1, but I do not have a Mac myself to verify this

That is correct :-). However it is also a great argument to DO include disk name and size in the confirmation popup to improve consistency.


Yes we can do that. I’ll add some logic to ask for the disc type to be USB etc. I’ll discuss this with dbmandrake, I know we had a similar discussion a while ago.


To follow up on this, I had a look at our installer.

In particular, osmc/io_osx.cpp at master · osmc/osmc · GitHub

shows that /dev/rdisk0 is excluded from the device selection. Which disk was showing as a ‘Macintosh HD’?

Hi it shows exactly:
Device Id Device Path Device Space
1 /dev/rd249.8 Macintosh HD
2 /dev/rdisk3 25.6 MB
(rdisk3 is the OSMC installer dmg)


Here is a screengrab


Seems that you have OS X installed on your second disk which is a little bit unusual. I will see what we can do about hiding the DMG.

Can you give us the output of

fdisk -l

Looks like some of our string processing has gone wrong there.

Second disk?

I only have one harddisk; this is on a retina macbook pro is there is not much space for a second disk :smile:


Ok – seems that the output parsing hasn’t worked too well. Can you upload output of the command as requested above?

-bash: fdisk-l: command not found

I assume you mistyped?

fdisk -l
fdisk: illegal option – l
usage: fdisk [-ieu] [-f mbrboot] [-c cyl -h head -s sect] [-S size] [-r] [-a style] disk
-i: initialize disk with new MBR
-u: update MBR code, preserve partition table
-e: edit MBRs on disk interactively
-f: specify non-standard MBR template
-chs: specify disk geometry
-S: specify disk size
-r: read partition specs from stdin (implies -i)
-a: auto-partition with the given style
-d: dump partition table
-y: don’t ask any questions
-t: test if disk is partitioned
`disk’ is of the form /dev/rdisk0.
auto-partition styles:
boothfs 8Mb boot plus HFS+ root partition (default)
hfs Entire disk as one HFS+ partition
dos Entire disk as one DOS partition
raid Entire disk as one 0xAC partition

Doesn’t seem to work quite either.

I forgot Mac OS X doesn’t allow listing of partitions this way. Try diskutil list

No problem :smile:

Here you go:

diskutil list

0: GUID_partition_scheme *251.0 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_CoreStorage 250.1 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
0: Apple_HFS Macintosh HD *249.8 GB disk1
Logical Volume on disk0s2
0: GUID_partition_scheme *25.6 MB disk3
1: Apple_HFS qt_host_installer 25.6 MB disk3s1

Many thanks, I’ll take a look at this shortly.

CC @srmo