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Re: cqcam-40b RPM
>Either the entire driver (in cqcam that would be port.o and camera.o) or
>nothing at all should be loaded into kernel space. I've kept cqcam
>entirely in user space for a few pretty good reasons.
True. For what I was doing, I didn't need much performance from the
parallel port.
>(An aside: the Solaris/x86 driver, if I write one, will require a kernel
>module, because user space programs can't do inb/outb. Annoying.)
i don't know much about the VM system on intel machines, but would it be
possible to write an mmap() entry point for /dev/lpt which mmaps io ports
into the address space of a user program? basically, this would provide the
exact functionality of ioperm(), but would actually be accessed through an
ioctl of the lpt driver. This way you get no performance hit on outb and inb,
and don't need to run your binaries suid (they just have to be able to open
/dev/lpt).
Ali.