Le Fri, 20 Jun 2014 18:44:35 +0530, Pranay Srivastava <pranjas@xxxxxxxxx> a écrit : > On Fri, Jun 20, 2014 at 6:29 PM, Harold André <harold.andre@xxxxxx> > wrote: > > Le Fri, 20 Jun 2014 16:36:58 +0530, > > Pranay Srivastava <pranjas@xxxxxxxxx> a écrit : > > > > > >> You say here you will define the function else where if > >> TEST_FUNCTION is defined > >> > >> > #ifdef TEST_FUNCTION > >> > void test(int *value); > >> > #else > >> > static inline void test(int *value) { } > >> > #endif > >> > > >> > test_ifdef.c: > >> > > >> > #include "test_ifdef.h" > >> > > >> But here you do on and define it any way. You must stick to the > >> rule you created earlier. If you are defining it here then this > >> must also be under the test of ifdef TEST_FUNCTION > >> > void test(int *value) > >> > { > >> > *value += 1; > >> > } > >> > > > > > Thank you Pranay for your answer. I understand this now. > > > > But when i look at the kernel code, i don't see ifdef test around > > the definition of the function. For example, i look for the function > > "hiddev_hid_event": > > > > In include/linux/hiddev.h: > > #ifdef CONFIG_USB_HIDDEV > > ... > > void hiddev_hid_event(struct hid_device *hid, struct hid_field > > *field, struct hid_usage *usage, __s32 value); > > ... > > #else > > ... > > static inline void hiddev_hid_event(struct hid_device *hid, struct > > hid_field *field, struct hid_usage *usage, __s32 value) { } > > ... > > #endif > > > > In drivers/hid/usbhid/hiddev.c: > > /* > > * This is where hid.c calls into hiddev to pass an event that > > occurred over > > That's right but the magic doesn't happen here :-) > > if you see usbhid/Makefile you'll understand what I mean :-). If not , > please do ask. Ah yes !! Ok, i understand !! ;-) Thank Pranay for sharing your knowledge ! _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies