143 the strange requirement to somehow set the stack limit first.
147 of the way we simply don't try to lock the memory at all.
174 /* check that we really dropped the privs.
203 * wipes out the memory on a free().
213 * But don't complain, as explained above.
488 * to make sure that the memory is wiped out.
491 * there is no chance to get the secure memory cleaned.