I know I'm being really dumb here, but what's the best way of returning two numbers from a C-function back to the main method?
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macOS Return two values (doubles) from a C function
- Thread starter Eraserhead
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There's no way to return more than one value.
The solution is to pass a pointer to a variable into your function, and set the value at that address in the function.
For example:
The solution is to pass a pointer to a variable into your function, and set the value at that address in the function.
For example:
Code:
void main()
{
double firstDouble, secondDouble;
firstDouble = function(&secondDouble);
// etc.
}
double function(double *doubleRef)
{
*doubleRef = 2.0;
return 1.0;
}Another solution...
The other solution would be to create a data structure with two doubles in it. You could do something like
I am a little rusty at C, but this is the basic idea and should work. In this case, you would get a reusable structure type defined to DoubleDouble.
The other solution would be to create a data structure with two doubles in it. You could do something like
Code:
typedef struct {
double one;
double two;
} DoubleDouble;I am a little rusty at C, but this is the basic idea and should work. In this case, you would get a reusable structure type defined to DoubleDouble.
From a semantics point of view, I would prefer to pass both variables by reference, or return a struct containing the two, rather than return one and pass the other by reference. It just seems cleaner this way.
Heh, DoubleDouble. That's how I take my coffee.
Heh, DoubleDouble. That's how I take my coffee.