Re: Basic C question

["rahul p" <rahulpyd@xxxxxxxxx>]

Manish,

It all looks pretty clear to me. In the first case  the 'get_block_t' structure is passed as an argument to the function. In the other case the pointer to the structure (get_block_t*) is passed as a function argument. I hope you know the difference between the 2. If not the following link would help.

http://www2.its.strath.ac.uk/courses/c/subsection3_12_3.html#SECTION00012300000000000000

-
Rahul Pydimukkala

On Sun, Aug 3, 2008 at 1:53 PM, Daniel Baluta <daniel.baluta@xxxxxxxxx> wrote:

See the definition of get_block_t

typedef int (get_block_t)(struct inode *inode, sector_t iblock,
                        struct buffer_head *bh_result, int create);

On 8/3/08, Manish Katiyar <mkatiyar@xxxxxxxxx> wrote:
> ok... I know i am going to be embarrassed but I am confused by the
> below function. The last parameter in do_mpage_readpage() is of type
> get_block_t, but when passed to block_read_full_page() it gets passed
> as get_block_t *.
>
>
> static struct bio * do_mpage_readpage(............., get_block_t get_block)
> {
>        ................
>        ................
>               if (page_has_buffers(page))
>               goto confused;
>         .................
> confused:
>               if (!PageUptodate(page))
>               block_read_full_page(page, get_block);
>        .........
> }
>
> int block_read_full_page(struct page *page, get_block_t *get_block) {
>         .........
>        ..........
> }
>
>
> How does this work ? :-( ....... Isn't gcc supposed to catch this and
> flag warning unless I am missing something very obvious.
>
> Thanks -
> Manish
>
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