[GRASS-dev] portable.h elimination

[Glynn Clements]

I've modified lib/vector/diglib to determine the byte ordering at run
time, rather than generating the portable.h header file.

The supplied test case passes. It might be useful to test it using dig
files generated on an architecture with the opposite byte order (I
have no way to test this). It might also be worth testing it on MinGW.

-- 
Glynn Clements <glynn at gclements.plus.com>