On Tue, Feb 19, 2013 at 5:04 PM, Florian Weimer fweimer@redhat.com wrote:
On 02/19/2013 04:32 PM, Jakub Jelinek wrote:
On Tue, Feb 19, 2013 at 09:22:55AM -0600, Eric Sandeen wrote:
(3) For my code that uses st_ino, I need to ensure this is never assigned to a 32 bit integer (eg. 'int', 'int32_t', 'long' on 32 bit, etc.)?
To be safe I'd use it in an u64 type, I guess. The *internal* kernel stat structure uses u64:
That would be wrong. To store st_ino values, you should be using the ino_t type, like for file sizes/offsets (st_size, seeking, etc.) you should be using off_t. Both of these types depend on _FILE_OFFSET_BITS macro.
You can't use ino_t and off_t in public header files because of that _FILE_OFFSET_BITS dependency. At least in such header files, using explicit 64-bit types (uint64_t, presumably) is the way to go.
Admittedly, this has a certain yuck factor, but I don't see a way around that.
To be safe and portable, use uintmax_t. It's still not quite pretty, but at least the type is portable, has a fixed ABI, and there are printf specifiers for uintmax_t (unlike ino_t or ino64_t). Mirek