What is the maximum size of any datatype based on the processor/operating system? How does this change across MacOS, Linux, Windows 9.x, WindowsNT and MS DOS?
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What is the maximum size of any datatype based on the processor/operating system? How does this change across MacOS, Linux, Windows 9.x, WindowsNT and MS DOS?
It varies though of the above msdos is the only one I know were 16bit int's were popular. Even then, watcom, for example, had 32bit int's (and pointers though you had to use DPMI). <limits> and <limits.h>/<climits> are your only way to be sure.
Maybe you can use sizeof(dataType) where dataType could be int, double, float, etc...
There is no limit to a size of a variable but speed is GREATLY decreses as size gets bigger or smaller than the cpu architecture size. On a 32-bit processor, 32-bit operations are faster than any other n-bit operations. That means that an int (or long int for those old compilers) will execute faster. On the newer Intel Itanium CPU series, which is 64-bits, longs will be faster.
For the no limits: You can infinitly add using the 'adc' asm instruction on x86 processors (add and carry).
However, on x86 and most other processors there are only 3 floating point sizes, 32 bits (float/single), 64 bits (double), 80 bits (long double (paragraph alligned)).
A struct can be a data type; I'm guessing what you mean are primitives, or int, short, float, etc. If that's not what you mean, then there is no limit.
right, Win32 has an INT64 defined for instance. not supported by the architecture but there are ways around that. It's really just a matter of how clever you want to be with your math. if you have a large buffer that you want to use for a huge integer you could do lots of things to work with that.