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SubjectRe: struct dirent in Linux 2.0

>> > > Unfortunately Linux currently defines just
>> > >
>> > > long d_ino;
>> > > __kernel_off_t d_off;
>> > > unsigned short d_reclen;
>> > > char d_name[256]; /* We must not include limits.h! */
>> > >
>Hmm, for one it's not 64 bit safe. Digital Unix (which does claim to be
>POSIX etc compliant) defines d_ino as an ino_t which is a uint_t which,
>in turn (bear with me) is a 'unsigned int', voila, it's 32 bits long.
>Happily the ext2 file definition (in include/linux/ext2_fs.h) gets it
>right (its an __u32)...

I always thought the purpose of abstract types like ino_t and off_t was
to provide a type whose length could vary between systems and over time
without needing application code rewrites, just a recompile.

By making d_ino long, aren't we shooting ourselves in the foot for when
we're running on systems with millions of terabytes of disk and need
shitloads of inodes? Yes, by that time we will probably have 128 or 256
bit longs, but we shouldn't be relying on that fact.

I know just how ridiculous it seems to ever want that many inodes, but
just think how big your hard drive was 10 years ago (if you had one at
all -- mine was 10MB). I expect Linux to still be around in another 10
years, and I expect similar or greater increases in storage capacities
(and decreases in physical size!).

Remember, Bill Gates once said he couldn't see why anyone would ever
need more than 640K RAM. How stupid does that sound now?

Also, surely __kernel_off_t is an internal kernel type, and shouldn't
be being used by userland applications. Abstracting this to off_t would
also promote portability between Linux and other versions of Unix.


PS. Does anyone what what (if anything) POSIX and/or the SUS have to say
about this?

``Anyone who cannot cope with mathematics is not fully human. He is at
best a tolerable subhuman who has learned to wear shoes, bathe and
not make messes in the house.'' -- from the notebooks of Lazarus Long
--------------------+--------------+---------------------------------------- | Micro$oft: | Linux, the choice of a GNU generation. | Just say no! | See for details

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