take a const 'name', since they dont modify anything.
159: warning: passing arg 1 of `getenv_int' discards qualifiers...
167: warning: passing arg 1 of `getenv' discards qualifiers from pointer..
around, use a common function for looking up and extracting the tunables
from the kernel environment. This saves duplicating the same function
over and over again. This way typically has an overhead of 8 bytes + the
path string, versus about 26 bytes + the path string.
parameter a char ** instead of a const char **. This make these
kernel routines consistent with the corresponding libc userland
routines.
Which is actually 'correct' is debatable, but consistency and
following the spec was deemed more important in this case.
Reviewed by (in concept): phk, bde
