On Thu, Oct 25, 2012 at 08:38:25PM -0700, Linus Torvalds wrote: > It's valid to cast a non-const pointer to a const one. It's the > *other* way around that is invalid. > > So marking fw_path[] as having 'const char *' elements just means that > we won't be changing those elements through the fw_path[] array > (correct: we only read them). The fact that one of those same pointers > is then also available through a non-const pointer variable means that > they can change through *that* pointer, but that doesn't change the > fact that fw_path[] itself contains const pointers. > > Remember: in C, a "const pointer" does *not* mean that the thing it > points to cannot change. It only means that it cannot change through > *that* pointer.
It's a bit trickier, unfortunately - pointer to pointer to const char and pointer to pointer to char do not mix. Just for fun, try to constify envp and argv arguments of call_usermodehelper()... -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/