Hi, On Sun, Jan 13, 2013 at 12:09 PM, horseriver <horserivers@gmail.com> wrote:
On Sun, Jan 13, 2013 at 09:27:45PM -0800, Dave Hylands wrote:
Hi,
On Sun, Jan 13, 2013 at 11:29 AM, horseriver <horserivers@gmail.com>
wrote:
hi:
In kernel code . some function is defined by
__attribute__((__section__(".initcall" level ".init")))
what does this do ?
It puts the address of the function in a linker section named .initcallX.init where X is replaced by the level.
why ".initcall" and level do not connect together with ## ? As I know , precompiler use ## to connect two strings
That's not quite true. ## is the token pasting operator and is for pasting together pieces of a token to create a larger token. http://gcc.gnu.org/onlinedocs/cpp/Concatenation.html If you have the tokens someVar_ and somethingElse you could token paste them together to make someVar_somethingElse The # operator is a for stringizing,which converts non-strings into strings. http://gcc.gnu.org/onlinedocs/cpp/Stringification.html#Stringification In C and C++ you can "paste" strings together by just putting them one after the other. const char *x = "This is a long string."; is 100% identical to const char *x = "This" " is a long " "string."; http://en.wikipedia.org/wiki/C_syntax#String_literal_concatenation -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com