lseek() fails to seek on /dev/fd0 ('\\.\A:')
Corinna Vinschen
cygwin-patches@cygwin.com
Tue Feb 27 03:02:00 GMT 2001
On Tue, Feb 27, 2001 at 12:45:39PM +0300, Egor Duda wrote:
> CV> Did you try that even on raw partitions (\\.\X:)? From the MSDN:
>
> CV> "The IOCTL_DISK_GET_DRIVE_GEOMETRY control code retrieves information
> CV> about the physical disk's geometry"
>
> CV> so I assume it will only work for raw harddisks (\\.\physicaldriveN).
>
> Yep, you're right. I can work around this with
> IOCTL_DISK_GET_PARTITION_INFO ioctl, but here comes the problem with
> off_t and size_t being long int :( So we won't be able to work with
> drives and partitions longer then 2G (which are very frequent
> nowadays). Should we return EINVAL in such cases?
I have just checked on Linux kernel 2.2.x. For some reason it returns
the following on partitions and physical drives:
lseek (fd, 0, SEEK_END) = 0 and the file pointer is set to the
beginning(!) of the raw device.
lseek (fd, pos != 0, SEEK_END) = -1 (EINVAL)
So if we want to be Linux compatible we could make our life very easy.
Has somebody a 2.4 kernel to test the behaviour there?
> BTW, does anybody have MO drives around to test this ioctls with
> partitioned removable media?
I have a ZIP-100 drive which is what you're looking for. I have
used it for testing the raw stuff earlier.
Corinna
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Corinna Vinschen Please, send mails regarding Cygwin to
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