Pointer to struct doesn't work properly?

Question

typedef struct Spheres{

    int PositionX;

    int PositionY;

    int Color;

    int Mass;

    int Radius;

    int SpeedX;

    int SpeedY;

}Sphere;



char readFile(FILE *file,Sphere **totalSphere){

    int positionX,positionY,color,mass,radius,speedX,speedY,amountOfSpheres,i;

    fscanf(file,"%d",&amountOfSpheres);

    *totalSphere=malloc(amountOfSpheres*sizeof(Sphere));

    for (i=0;i<amountOfSpheres;i++){

        fscanf(file,"%d%d%d%d%d%d%d",&positionX,&positionY,&color,&mass,&radius,&speedX,&speedY);

        totalSphere[i]->PositionX=positionX;

        totalSphere[i]->PositionY=positionY;

        totalSphere[i]->Color=color;

        totalSphere[i]->Mass=mass;

        totalSphere[i]->Radius=radius;

        totalSphere[i]->SpeedX=speedX;

        totalSphere[i]->SpeedY=speedY;

    }

    printf("%d %d %d %d %d %d %d\n",totalSphere[0]->PositionX,totalSphere[0]->PositionY,totalSphere[0]->Color,totalSphere[0]->Mass,totalSphere[0]->Radius,totalSphere[0]->SpeedX,totalSphere[0]->SpeedY);

    printf("%d %d %d %d %d %d %d\n",totalSphere[1]->PositionX,totalSphere[1]->PositionY,totalSphere[1]->Color,totalSphere[1]->Mass,totalSphere[1]->Radius,totalSphere[1]->SpeedX,totalSphere[1]->SpeedY);

}





int main()

{

    FILE *file;

    Sphere *totalSphere;

    totalSphere=NULL;

    if ((file=fopen("input.txt","r"))!=NULL){

        if (readFile(file,&totalSphere)){

            printf("%d %d %d %d %d %d %d\n",totalSphere[0].PositionX,totalSphere[0].PositionY,totalSphere[0].Color,totalSphere[0].Mass,totalSphere[0].Radius,totalSphere[0].SpeedX,totalSphere[0].SpeedY);

            printf("%d %d %d %d %d %d %d\n",totalSphere[1].PositionX,totalSphere[1].PositionY,totalSphere[1].Color,totalSphere[1].Mass,totalSphere[1].Radius,totalSphere[1].SpeedX,totalSphere[1].SpeedY);

            fclose(file);

    return 0;

}

This is my code and
this is the text file i'm reading from

The problem is that when the function readFile() ends, the values from totalSphere[1] are lost as you can see here but the values from totalSphere[0] are ok. Why is this happening?

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Answer 1

You got lost in levels of indirection, apparently. The array of Sphere objects that you allocated inside readFile is supposed to be accessed as (*totalSphere)[i]. E.g

for (i = 0; i < amountOfSpheres; i++) {
  fscanf(file, "%d%d%d%d%d%d%d", &positionX, &positionY, &color, &mass, &radius, &speedX, &speedY);
  (*totalSphere)[i].PositionX = positionX;
  (*totalSphere)[i].PositionY = positionY;
  ...

Your original version is incorrect.

The (*totalSphere)[i] syntax applies inside readFile, since totalSphere is Sphere ** there. In main you will access the received array the "regular" way - as totalSphere[i].

Pointer to struct doesn't work properly?

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