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/proc/partitions question


Sorry, lost the previous mail so can't continue the thread.

I took a look at the sources as cgf suggested and
have the following question:

in fhandler_proc.cc revision 1.36,
in function format_proc_partitions() :

after getting the drive geometry with
'IOCTL_DISK_GET_DRIVE_GEOMETRY'
the size of the disk is calculated in bytes and this number is
right-shifted 6 bits, so that's a division by 64 and that maps
with the scaling difference of 16 between df and /proc/partitions.

likewise after getting the drive's partition layout with
'IOCTL_DISK_GET_DRIVE_LAYOUT'
the length of each parititions (which is in bytes) is again
right-shifted 6 bits.

So why the right-shift 6 instead of 10 which would map
with a blocksize of 1K?

If this is an obvious or trivial thing or if this has been
addressed on the mailing list before or on some
website: I apologise. I'm neither a windows nor a cygwin
developer and I have little time but this just struck me
as a bit weird.

Erik.

PS: if the layout of this mail looks weird I blame it
on Lotus Notes which I am forced to use here at work. :(


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