Re: time stamp resolution

Marek Michalkiewicz (
Thu, 14 Nov 1996 18:03:47 +0100 (MET)

Rob Hagopian:
> 32-bit device numbers! I _need_ this! (if there's anything I can do to
> further this along, I'm more than willing)

Yes - HP-UX already has them (8 bits major + 24 bits minor).
One nice thing is that "ls" shows minor numbers in hexadecimal,
so it's easy to decode the bits (for example: SCSI controller,
ID, LUN, partition numbers). Some other drivers use the extra
bits to enable various features (like tty drivers allowing open
without raising DTR/RTS).

> kdev_t.h:
> /* Since MINOR(dev) is used as index in static arrays,
> the kernel is not quite ready yet for larger minors.
> However, everything runs fine with an arbitrary kdev_t type. */

Is this right? Are minor (not major) numbers still used this way?
(Major would be OK if it's only 8 bits.)