On Tue, Mar 22, 2016 at 01:17:42PM +0100, Serge van den Boom wrote: > 1. 'partx --nr 1:' does not work. Fixed. # partx --show --nr 1: /dev/sdc NR START END SECTORS SIZE NAME UUID 1 2048 22527 20480 10M fa3974fc-40a2-402a-941a-7d26b32e126d 2 22528 43007 20480 10M 808a2e20-7109-4f2f-9727-f474f5119231 4 63488 83967 20480 10M 8fe134d1-af94-48d0-94f2-9b757da8731f > 2. 'partx --nr <M:N>' does not take empty partition table entries into > account when using negative indexes. ... > One might expect that 'partx --nr 1:-1' would list all partitions (i.e. > from the first to the last partition), but this is currently not true in > this case: > > $ partx --nr 1:-1 testfile > NR START END SECTORS SIZE NAME UUID > 1 2048 10000 7953 3.9M 4fafc399-01 Fixed. Note that --nr specifies partno (column NR), rather than seq.number. Unfortunately, code mixed partno and seq.number of the partition. # partx --show --nr 1:-1 /dev/sdc NR START END SECTORS SIZE NAME UUID 1 2048 22527 20480 10M fa3974fc-40a2-402a-941a-7d26b32e126d 2 22528 43007 20480 10M 808a2e20-7109-4f2f-9727-f474f5119231 4 63488 83967 20480 10M 8fe134d1-af94-48d0-94f2-9b757da8731f > In fact, 'partx --nr -1:-1' returns no output at all. Fixed. # partx --show --nr -1:-1 /dev/sdc NR START END SECTORS SIZE NAME UUID 4 63488 83967 20480 10M 8fe134d1-af94-48d0-94f2-9b757da8731f > 3. It is not always clear whether a single partition table entry refers > to the partition table on the block device, or to a partition table > entry of the block device of which the specified block device is a part. > > When the specified block device contains a partition table, that > partition table is shown. When it does not contain a partition table, > but the block device is a partition itself, its entry on its parent > block device is shown. When you don't know whether a given block device > contains is a full disk or a partition (because you're calling partx > from a script) special logic would be required. Also, nested partition > tables are theoretically possible, though unusual. You have to always specify partition (-nr or devname), whole-disk is optional. If you want to read partitioned partition (nested PT) then you can use '-' instead of partition name: partx --show - /dev/sdc1 Anyway, my suggestion is to use sfdisk if you want complicated things like nested partitions. > As a work-around, something like 'partx --nr 1:65535' may be used if > you are interested in the partitions of the specified block device > itself. 'partx --nr 1:' would avoid the arbitrary upper bound, but does > not work because of issue 1, and 'partx --nr 1:-1' would too, but does > not work because of issue 2. --nr 1: and --nr 1:-1 works now > 4. It is possible to specify a partition by the device name of a > partition on another block device. > > The command 'partx /dev/sdb2 /dev/sda' makes no sense, but still > produces output, namely the second partition of /dev/sda. Fixed, # partx --show /dev/sdx1 /dev/sdc partx: partition and disk name do not match I'll prepare regression test for partx.... -- Karel Zak <kzak@xxxxxxxxxx> http://karelzak.blogspot.com -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
