标题: What's the difference between NULL and 0 in 2.4 kernels? [打印本页] 作者: daiban 时间: 2007-01-25 13:04 标题: What's the difference between NULL and 0 in 2.4 kernels? In 2.4 kernels, what's the difference between NULL and 0? I know at least one place that these two behave differently. The function remove_proc_entry() takes two arguments, the first the name of the filenode, the second is the pointer to the parent directory, a NULL pointer means that filenode is directly under /proc directory. Now is the interesting part. The following function call
remove_proc_entry("scullpmem", NULL);
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correctly removes the /proc/scullpmem file, while the next form
remove_proc_entry("scullpmem", 0);
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doesn't work.
In the kernel source, NULL is defined as ((void *) 0).
Then what's the difference between NULL and 0? Thanks in advance.
Sorry for troubling all you guys by this meanlingless question. Last Night I dug into the source code and found nothing interesting. In fact, by redoing the experiments I have got to know that the second form also worked. The malfunction must be caused by some reason, though not known yet.
Best Regards
[ 本帖最后由 daiban 于 2007-1-26 12:46 编辑 ]作者: fuyic 时间: 2007-01-25 14:45
帮顶，看看高人对这个的解释作者: fuyic 时间: 2007-01-25 18:51
楼主都不关心，我继续帮顶作者: daiban 时间: 2007-01-25 21:07
To fuyic: I'm keeping an eye on this, ha ha.
Planing to read the fucking source code, and dig it out.