"tar tfv /dev/cd0" speedup patch

Jung-uk Kim jkim at FreeBSD.org
Sat Feb 20 06:01:05 UTC 2010


On Saturday 20 February 2010 12:20 am, Tim Kientzle wrote:
> Juergen,
>
> I was looking at your Linux code here and thought
> the technique of trying lseek(SEEK_END) might work.
> Unfortunately, it doesn't: lseek(fd, 0, SEEK_END) gives
> zero for both /dev/sa0 (a tape drive) and /dev/cd0
> (an optical drive).  Are you sure it works on Linux?

Can you please try ioctl(fd, BLKGETSIZE64, &some_uint64_var) or 
ioctl(fd, BLKGETSIZE, &some_u_long_var)?

Jung-uk Kim


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