c,function,pointers,struct , How to pass pointer to struct to a function?

How to pass pointer to struct to a function?


Tag: c,function,pointers,struct

I am instantiating the struct within the main() function and I am passing a pointer to this structure over to a function. I would like to then pass this pointer to the original struct to another function, how would I do this?

I am now lost in pointerception.

struct coords {
    int x;
    int y;

// Main loop, instantiated the struct
int main(void)
    struct coords myCoords;
    while(1) {

// Calculate Coords and update them via pointer to struct
// I want to be able to edit myCoords within calculateCoords
void doStuff(struct coords* myCoords)


// I want to be able to edit myCoords within here!
void calculateCoords(struct coords* myCoords)
    myCoords->x = 100;


Inside your doStuff() function, myCoords is already a pointer. You can simply pass that pointer itself to calculateCoords() and calculateMotorSpeeds() function.

Also, with a function prototype like

 void calculateCoords(struct coords* myCoords)



from doStuff() is wrong, as it is passing struct coords**.


Keep your function signature for calculateCoords() intact, just chnage the call to


and then, any changes made to any member variable through myCoords inside calculateCoords will be reflected in the myCoords in main().


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