Using <linux/types.h> in user programs, or <stdint.h> in driver module code...does it matter?
- Is it a bad idea to use linux/*.h includes in user-space code?
Yes, usually. The typical situation is that you should be using the C-library headers (in this case, stdint.h and friends), and interface with the C library though those user-space types, and let the library handle talking with the kernel through kernel types.
You're not in a typical situation though. In your case, you're writing the driver library. So you should be presenting an interface to userspace using stdint.h, but using the linux/*.h headers when you interface to your kernel driver.
So the answer is no, in your case.
- Is it a bad idea to use stdint.h in kernel-space code?
Most definitely yes.
See also: http://lwn.net/Articles/113349/