Comment 12 for bug 906722

Right, the change in behavior is due to commit e82810c6cf3fe94d2cf70d485a59c411ccb601b3 upstream; prior to this, sfdisk evidently was *never* noticing a failure of the partition rereading. And '--no-reread' is only defined to suppress checking if the disk is in use, it says nothing about suppressing the attempt to force a reread of the partition table afterwards.

Likewise, --force is defined as disabling consistency checking, allowing you to override problems that sfdisk would normally complain about and continue with an operation that it considers unsafe. In this case, the failed ioctl doesn't prevent sfdisk from making any changes, it *only* impacts the error code from sfdisk at the end.

So I think the behavior of 2.20 is consistent and should not be changed, even though the behavior differed in the past.