kread() and NULL pointers
Mike Mason
mmlnx@us.ibm.com
Mon Jul 16 23:10:00 GMT 2007
Roland McGrath wrote:
>> Does kread() generate an error if you pass it a NULL pointer?
>
> Yes. It's safely caught like all errors, but it only returns successfully
> when given a valid pointer.
So should the following generate an error? It doesn't. It just prints "ptr = 0" and exits.
function test_addr:long () %{
void *nullptr = NULL;
THIS->__retvalue = (long) kread(&(nullptr));
CATCH_DEREF_FAULT();
%}
probe begin {
ptr = test_addr()
printf("ptr = %d\n", ptr)
exit()
}
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