for the new environment-manipulation done at startup. Move the routines
from being local to tls.c to being global via the os.c file.
+JH/48 Bug 1807: Fix ${extract } for the numeric/3-string case. While preparsing
+ an extract embedded as result-arg for a map, the first arg for extract
+ is unavailable so we cannot tell if this is a numbered or keyed
+ extraction. Accept either.
+
Exim version 4.86