It sounds like you're reinventing LC_NUMERIC. The locale system has a lot more than just LANG; it already allows the number format to be overridden separately from the "language". Take a look at `locale -k LC_NUMERIC` and < https://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap07.html>.
Adding custom variables would require changing a lot – I guess the main consumers are libc (Glibc) and libstdc++ (GCC), but of course there are many places which set the existing LC_* and expect things to change accordingly, or which might implement the standard interfaces on their own without using libc. On Tue, Aug 29, 2023, 20:17 TJ Shipp <onezoo...@msn.com> wrote: > I am trying to add in support for a separate variable to change our unit > system, and having both LANG and UNITS to identify the "locale" of the > system. > We are also not only looking for English versus Metric, but are looking > for mixed units as well (both Imperial and Metric hybrid), as well as > looking to add number formats (1,000.00 vs 1.000,00) > > And what is the best way to add support for a new system environment > variable such as UNITS? > > P.S. If anyone is interested in contracting to do this work, please send > me a private message outside this list. >