On 11/11/17 12:08, David Durham wrote: > sudo tail -c 1024 /dev/sda2 | hd the entire /dev/sda2 device rather than > seeking to the end. This takes a very long time with large disks. Deltik > gives a nice explanation here - > https://superuser.com/questions/1267402/how-do-i-tail-a-block-device-in-linux > - of how ioctl can be used to obtain the size of a block device instead of > fstat. > > <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon> > Virus-free. > www.avast.com > <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link> > <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> >
Yes maybe. The answer at the link shows how to do it efficiently with the existing `dd` and `blockdev --getsize64` tools. I also mentioned there the iflag=skip_bytes option which allows one to efficiently skip portions of a disk independently from the I/O size. Given dd is a more natural tool for dealing with device I/O, and that processing the end of a device is an unusual use case, I'm on the fence as to whether `tail` should handle this case specially. cheers, Pádraig
