Bug - Preallocation Behavior in ddrescue

[Barry Jones]

I've noticed strange behavior related to the --preallocate argument in
ddrescue. I typically output to an image file on an NTFS volume. When I use
the --preallocate argument, it takes several hours to create the
preallocated image file. Conversely, if I omit the --preallocate argument
and use the --reverse argument, the full-sized image file gets created
almost immediately. I'm not using the --sparse argument in either case.