Hi,
I noticed some kernel .c files #include <version.h> which typically
contains something like:
#define UTS_RELEASE "2.6.9-rc1"
#define LINUX_VERSION_CODE 132617
#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
However, those files don't reference the macros.
The question is: are these includes completely unneeded, so I can
remove them, or do they serve some special purpose?
Another one: there are drivers using constructs like:
#if LINUX_VERSION_CODE > 0x20115
...
#endif
I understand they can be somehow useful for authors supporting many
kernel versions with a single set of files, however the gain isn't
clear to me. Should such conditional code be a) removed, b) left
in place, c) dealt with each case individually?
--
Krzysztof Halasa
On Tue, Sep 07, 2004 at 06:17:53PM +0200, Krzysztof Halasa wrote:
> Hi,
Hi Krzysztof,
> I noticed some kernel .c files #include <version.h> which typically
> contains something like:
>
> #define UTS_RELEASE "2.6.9-rc1"
> #define LINUX_VERSION_CODE 132617
> #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
>
> However, those files don't reference the macros.
>
> The question is: are these includes completely unneeded, so I can
> remove them, or do they serve some special purpose?
they don't serve any special purpose.
But please doublecheck that they are really not needed.
> Another one: there are drivers using constructs like:
>
> #if LINUX_VERSION_CODE > 0x20115
> ...
> #endif
>
> I understand they can be somehow useful for authors supporting many
> kernel versions with a single set of files, however the gain isn't
> clear to me. Should such conditional code be a) removed, b) left
> in place, c) dealt with each case individually?
c)
Many driver authors share their code this way between different major
kernel versions, which makes it easier for them to maintain their code.
#ifdef's for kernel 2.4 are often still actively maitained.
#ifdef's for kernel 2.2 are only very rarely actively maitained.
#ifdef's for kernel 2.0 (as in your example) are most likely completely
obsolete.
> Krzysztof Halasa
cu
Adrian
--
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of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed