System Dependence
=================

   The code is carefully segregated into a system independent portion
and a system dependent portion.  The system dependent code is in the
`unix' subdirectory, and also in the file `sysh.unx' (also known as
`sysdep.h').

   With the right configuration parameters, the system independent code
calls only ANSI C functions.  Some of the less common ANSI C functions
are also provided in the `lib' directory.  The replacement function
`strtol' in `lib/strtol.c' assumes that the characters `A' to `F' and
`a' to `f' appear in strictly sequential order.  The function
`igradecmp' in `uuconf/grdcmp.c' assumes that the upper and lower case
letters appear in order.  Both assumptions are true for ASCII and
EBCDIC, but neither is guaranteed by ANSI C.  Disregarding these
caveats, I believe that the system independent portion of the code is
strictly conforming.

   That's not too exciting, since all the work is done in the system
dependent code.  I think that this code can conform to POSIX 1003.1,
given the right compilation parameters.  I'm a bit less certain about
this, though.

   The code has been used on a 16 bit segmented system with no function
prototypes, so I'm fairly certain that all casts to long and pointers
are done when necessary.