Hello Neil

I've modded mdadm's ouptut (see below for example)

* adds a blank line after 'Raid Devices' disks to visually show those in 
the array and those not (sounds trivial but actually helped me 
understand the output a lot better)
* parses /proc/mdstat and indicates which disk is rebuilding

It would be nicer if the GET_DISK_INFO ioctl could return more info into 
but I have no real idea how to approach this. What are the issues about 
adding to the ioctl interface?
(just been looking through md.c to find out what info is there though... 
and there's a lot to tell userland)

Anyway sample output:

/dev/md0:
        Version : 00.90.01
  Creation Time : Fri Jun  4 13:03:09 2004
     Raid Level : raid5
     Array Size : 2939520 (2.80 GiB 3.01 GB)
    Device Size : 979840 (956.88 MiB 1003.36 MB)
   Raid Devices : 4
  Total Devices : 5
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Fri Jun  4 15:44:47 2004
          State : clean, degraded, recovering
 Active Devices : 3
Working Devices : 4
 Failed Devices : 1
  Spare Devices : 1

         Layout : left-symmetric
     Chunk Size : 128K

 Rebuild Status : 2% complete

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       8       17        1      active sync   /dev/sdb1
       2       0        0       -1      removed
       3       8        2        3      active sync   /dev/sda2

       4       8       34        2      rebuilding spare   /dev/sdc2
       5       8       33       -1      faulty   /dev/sdc1
           UUID : f06ab9bd:c29b9f86:12b668e4:84c7333b
         Events : 0.6390

Here's the patch, I'm no C expert so you'll want to double check :)
(I'd appreciate any feedback too)

David