Messages in this thread | | | Subject | Question with "container_of(ptr, type, member)" | From | peter <> | Date | Tue, 30 Aug 2011 18:44:59 +0800 |
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I have a question about the macro " container_of(ptr, type, member) " I can write it as this, #define container_of(ptr, type, member) ({ \ (type *) ((char *) ptr - offset_of(type, member)); \ }) It can act the same as #define container_of(ptr, type, member) ({ \ const typeof( ((type *)0)->member ) *__mptr = (ptr); \ (type *)( (char *)__mptr - offsetof(type,member) );}) So why we don't use the first one ? Thanks for your answer. (I am a kernel newbie ,and sorry for my poor english~)
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