Hi Vichy
I found there are 2 errno.h we can include when coding.
#include <asm-generic/errno.h> and #include <linux/errno.h>
is there difference or rue I need to follow when I want to take
advantage of errno in kernel?
Looking at my sources you should use linux/errno.h. When I look, I see the following:
linux/errno.h:
#ifndef _LINUX_ERRNO_H
#define _LINUX_ERRNO_H
#include <asm/errno.h>
#endif
asm/errno.h:
#include <asm-generic/errno.h>
asm-generic/errno.h:
#ifndef _ASM_GENERIC_ERRNO_H
#define _ASM_GENERIC_ERRNO_H
#include <asm-generic/errno-base.h>
#define EDEADLK 35 /* Resource deadlock would occur */
#define ENAMETOOLONG 36 /* File name too long */
#define ENOLCK 37 /* No record locks available */
#define ENOSYS 38 /* Function not implemented */
...
So, it only makes sense to use linux/errno.h in my opinion.
Hope this helps,
Michael
Michael F Clarke
MEng Software Engineering