For space efficiency, I have decided to code my save files using binary. Every byte represents an id for the type of tile. Would this cause an issue with different Endian computing?
Also, out of curiosity, is it the CPU or the operating system which sets the Endian type?
Additional information: I am using C++ and building an x-platform game. I do not want to use an additional API such as Boost.
Yes, it will cause issues – if the saved file from BE gets loaded on LE or vice versa. This is why some Unicode encodings such as UTF-16 and UTF-32 have a so-called byte-order marker.
If your code is usually compiled on BE you will still have to make sure that the LE code will swap the byte order before making use of the data.
The CPU sets the Endianess and some chips (e.g. some MIPS CPUs) allow that to be switched when bootstrapping the system.