I have an alternate suggestion: what about continued fractions? Turn the floating point value into a list of integers. This works no matter what f.p. systems the source and destination use. You just need a portable integer serialization format.
Then why cannot we use IEEE745 format for float serialization on all systems? 1. If a systems is IEEE745 compatible, serialize float numbers directly. This will work 99.9% of the times, and will be very efficient. 2. If a system is not IEEE745 compatible, to serialize a float number, we write the number as 32 or 64 continuous bits, in IEEE745 format, to de-serialize a float number, we read the number in IEEE745 formats and write in native float format. An intermediate string representation can be used for the translations. I mean, these continuous IEEE745 bits are equivalent to your "portable integer serialization format", but will be much more efficient on IEEE745 compatible systems. Cheers, Bo