Messages in this thread | | | Date | Mon, 31 May 2004 22:11:20 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | Re: How to use floating point in a module? |
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On Sun, 30 May 2004 ndiamond@despammed.com wrote:
> A driver, implemented as a module, must do some floating-point > computations including trig functions. Fortunately the architecture > is x86. A few hundred kilograms of searching (almost a ton of searching :-) seems to reveal the following possibilities. >
Since you are using one of those Windows mailers and didn't enter a single end-of-line character, I detect that this is probably one of those trolls. Nevertheless, the use of floating-point is forbidden within the kernel. Period. Because anybody who thinks they need floating-point mathematics within the kernel is completely without a clue, the floating-point context is not saved/restored during system calls.
You must pair a user-mode program (usually called a daemon) with the kernel-mode interface to your hardware (your module). This combination will provide whatever functionality you require. The user-mode daemon does the math and probably a lot of other things as well.
Cheers, Dick Johnson Penguin : Linux version 2.4.26 on an i686 machine (5583.66 BogoMips). Note 96.31% of all statistics are fiction.
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