Difference between \??\ and \\?\

[DSF]

Hello all,

When I call DeviceIoControl with FSCTL_GET_REPARSE_POINT as an
argument, all mount and junction points returned are prefixed with
"\??\" which is not even suitable for use with
GetVolumePathNamesForVolumeName() to get a list of drive letters /
mount points. I must convert it to \\?\ first. So my question is
what is \??\ used for? (I know the purpose of \\?\.)

Since there doesn't seem to be a search engine out there that deals
with \??\ or \\?\, I thought I'd ask here.

Thanks,
DSF

P.S. If I ever have time, I must look into the algorythms for spelling
checkers. The one in Agent wants to replace
"GetVolumePathNamesForVolumeName" with "Extolment." :)

[Ant]

"DSF" wrote:

> When I call DeviceIoControl with FSCTL_GET_REPARSE_POINT as an
> argument, all mount and junction points returned are prefixed with
> "\??\" which is not even suitable for use with
> GetVolumePathNamesForVolumeName() to get a list of drive letters /
> mount points. I must convert it to \\?\ first. So my question is
> what is \??\ used for? (I know the purpose of \\?\.)

\?? is the name of the Win32 object namespace. It's used when passing
names to native and kernel mode routines. It's symbolic link name is
\DosDevices.

[DSF]

Thank you,
DSF