Can't successfully compile Scull - an example in "linux driver development"

[CoolEagle]

I am new commmer for linx wonderful world and I am learning "linux driver development".

an example called scull on the chapter 3, I was not able to successfully compile it. there are a lot of errors.

So i found answers from google. a guy said:"comment out the following content" in Rules.make

I did, cool, i can successfully compile Scull and Scull work well.

I just wonder:
1.Is there any risk by commenting out the following content?
2. why Scull can be successfuly compiled by commenting out the following content?


Thankyou very mcuh!

## We need the configuration file, for CONFIG_SMP and possibly other stuff
## (especiall for RISC platforms, where CFLAGS depends on the exact
## processor being used).
#ifeq ($(KERNELDIR)/.config,$(wildcard $(KERNELDIR))/.config)
# include $(KERNELDIR)/.config
#else
# MESSAGE := $(shell echo "WARNING: no .config file in $(KERNELDIR)")
#endif

[coopstah13]

This book was written around kernel 2.6.8, lots of things have changed since then and I imagine that is not the kernel you are running and trying to compile against.

[CoolEagle]

Yes, I was running it at Kernel2.4.20-8

[coopstah13]

2.4 kernel is even older, are you reading the 2nd or 3rd edition of the book? The 3rd edition is for kernel with 2.6, 2nd edition is for 2.4 kernel I think