Messages in this thread | | | Date | Mon, 10 Jun 2002 14:17:35 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | Re: procedure for creating new ioctl? |
| |
On Mon, 10 Jun 2002, Joseph Cheek wrote:
> hi all, > > i'd like to create a new ioctl for use in my kernels [actually i already > have 8-)] but want to make sure that i follow any established procedure > for creating it before requesting it be included in the kernel. > specifically, is there a way to ensure the ioctl number i use isn't in > use by anyone else? is there a central registry? > > so far i've just picked an arbitrary number: > > sanfrancisco:/usr/src/linux-2.4.17/include/linux# diff -Naur kd.h{.orig,} > --- kd.h.orig Mon Jun 10 11:08:22 2002 > +++ kd.h Thu Jun 6 16:00:33 2002 > @@ -177,4 +177,6 @@ > don't reuse for the time being */ > /* note: 0x4B60-0x4B6D, 0x4B70-0x4B72 used above */ > > +#define KDGETKEYDOWNSTATE 0x4B80 /* read kernel keydown bit */ > + > #endif /* _LINUX_KD_H */ > > any tips, pointers appreciated. > > joe >
I use SIOCDEVPRIVATE as the starting value for new ioctls:
/* * Interface to the private device functions. User API sees this only. */ #define CHEK_SEEPROM SIOCDEVPRIVATE + 0x07 #define READ_SEEPROM SIOCDEVPRIVATE + 0x08 #define WRITE_SEEPROM SIOCDEVPRIVATE + 0x09
I've seen this in several drivers. I think this is the way to do it so there is no interference with other ioctls.
Cheers, Dick Johnson
Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips).
Windows-2000/Professional isn't.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |