On Wed, Apr 16, 2008 at 7:01 PM, Pádraig Brady <[EMAIL PROTECTED]> wrote: > dd handles skip weirdly > > disk=/dev/sda8 > dd if=$disk bs=8M count=1 skip=1000 of=/dev/null #ok > dd if=$disk bs=8M count=1 skip=1000K of=/dev/null #reads whole disk! as seek > fails > > I had a 10s look at the source and noticed a comment > saying POSIX doesn't specify what we should do when > skipping past the end of input. For seekable files though, > reading the whole thing is unexpected to me at least. > I would expect it to do: > > if (seekable && !seek(skip_len)) > exit(EXIT_FAILURE);
It looks me that the offset is too large? strace shows: _llseek(0, 8589934592000, 0xbff7efb0, SEEK_CUR) = -1 EINVAL (Invalid argument) Where as strace dd if=/dev/hda2 of=/dev/null bs=8M skip=10 shows: _llseek(0, 83886080, [83886080], SEEK_CUR) = 0 I agree that I would expect if the file is seekable and seek fails, dd would exit. But here it looks like we just cannot seek that large of an offset? Respectfully, Brock _______________________________________________ Bug-coreutils mailing list Bug-coreutils@gnu.org http://lists.gnu.org/mailman/listinfo/bug-coreutils
