Re: I.1 - System calls - ioctl

Arnd Bergmann
2009-07-30T17:21:27Z

On Thursday 30 July 2009, stephane eranian wrote:
> But that won't always work in the case of a 32-bit monitoring tool
> running on top of
> a 64-bit OS. Imagine the target id is indeed 64-bit, e.g., inode
> number (as suggested
> by Peter). It's not because you are a 32-bit tool than you cannot name
> a monitoring
> resource in a 64-bit OS.

Right, there are obviously things that you cannot address with
a 'long', but there are potentially other things that you could
that you cannot address with an 'int', e.g. an opaque user
token (representing a user pointer) that you can get back in
the sample data.

In the worst case, you could still redefine the argument as a
transparent union to a long and pointer in the future if you
use a 'long' now. AFAICT, there are no advantages of using
an 'int' instead of a 'long', but there are disadvantages of
using a 'long long'.