On Sat, 2023-07-08 at 20:13 -0700, Samuel Sieb wrote: > On 7/8/23 13:47, Barry wrote: > > > On 7 Jul 2023, at 18:43, home user <mattisonw@xxxxxxxxxxx> wrote: > > > > > > When I try to verify a back-up, I use "diff -r". The directory > > > trees being compared contain about 870 files (mostly binary, like > > > PNG, JPG, and so on), and take up about 707 megabytes. The trees > > > being compared are on the hard drive and on a USB-3 stick. When > > > I run the "diff -r" command, it seems to finish too quickly - it > > > seems like less than a half of a second. I saw similar results a > > > few weeks ago comparing about 30 gigabyte trees on the hard drive > > > vs. on a USB-3.1 stick; the results were practically > > > instantaneous. Is diff actually checking every bit (or byte), or > > > is it using some "short cut"? > > > > I recall that for a file is equal test cmp is the command to use > > not diff. > > That was mentioned in an earlier message. cmp doesn't have a > recursive > option and diff works just fine for binary files. Since diff works in terms of lines, what if there are no newline bytes in the files? Could diff have an internal buffer overflow? poc _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
