Hi all, I'd like to make some code which can compile with no issues both with x86 (32-bit) and amd64(64-bit) code generation, under g++/gcc. Now what I have learned is that: in 32bits, pointers, ints, float and longs are 4 bytes doubles are 8 bytes in 64bits, pointers and longs are 64 bits and ints are 32bits what other issue are there? are floats still 4 byte in 64-bits (I am pretty sure it should be, but you never know) and are doubles still 8 bytes? also, if one compiles using openGL's standard header files, eg <Gl/gl.h>, ect that are on the _user's_ systems do the openGL types change sizes? this might be an issue with some openGL calls if the types do change sizes..... now if I stick to say using GLint, GLshort, GLbyte, GLfloat, would I be safe? the main worry I have is reading in binary data files.... I don't even want to think about porting to Mac's easily (due to Big vs Little Endian issues) wit repsect to reading binary data files... though I imagine that floats and doubles should not change.. or do they? I know ints, longs have a different byte order on Mac's.... and to make life as best as possible I do not have access to an amd64 machine Best Regards

Also keep in mind that the int/long sizes you mention are not carved in stone. 64-bit compilers for Windows use a 32-bit long.

Hi,

thanks for the poitner to stdint.h (I should haev realized this!) however, anyone know what the dfference between the "fast" and "least" types in it? for my system it looks like they are the same, but for others?