Normally these are set to size_t and ssize_t. But if they do not
exist, then they are set to the smallest integer type that can
contain a pointer. size_t is unsigned and ssize_t is signed.
This avoids warnings in OpenBSD that apparently can't be turned
off whenever you link strcpy, strcat, or sprintf. When snprintf
isn't available, the use of the "unsafe" string functions has
always in fact been safe, since the lengths are all checked before
those functions are called.
We do not use strlcpy or strlcat, since they are not (yet) found on
all systems. snprintf on the other hand is part of the C standard
library and is very common.
