Portability

The basic behavior of CLASS is that it loads all the user subsections (if any) at read time, and transfer all of them to the output file at write time. However, the data block of bytes is untyped in the CLASS data format, so it will make sense to re-read them if and only if the reading machine has the same endianness (IEEE, EEEI, etc) than the one used at write time. As a consequence the following restrictions apply:

1. at read time, CLASS won't read the user section if the input file type is not native (i.e. it has not been written under the same architecture we are reading it),
2. at write time, CLASS won't write the user section if the output file type is not native (i.e. we reopened for output a file first written under another architecture).

However, these restrictions have very low chance to occur, since nowadays most (all?) of the computers have an IEEE architecture.