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POpointers to structs inside union: how to initialize and retrieve struc values
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2013-09-09T09:54:54.947
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I have the following simple code. I am trying to understand how I can use structs inside unions and how I can retrieve contents of struct variables in connection with unions. Here is a small sample code I have written. I want to retrieve the "Maker" struct variables from this code. How should I correctly do it? My code here results in segmentation fault. Here is the updated code : <pre><code>#include <stdio.h> #include <stdlib.h> typedef struct{ char *name; int *wheels; }CarVendor; typedef struct{ char *name; int *wheels; int seats; }BusVendor; typedef union{ CarVendor *carvendor; BusVendor *busvendor; }Maker; typedef struct{ Maker *carType; }Car; typedef struct{ Maker *busType; }Bus; typedef union{ Car *car; Bus *bus; }Vehicle; void fillDetails(Vehicle *vehicle, int type){ if(type == 0){ vehicle->car->carType->carvendor->name = "car"; int wheel = 4; vehicle->car->carType->carvendor->wheels = &wheel; } if(type ==1){ vehicle->bus->busType->busvendor->name = "bus"; int wheel = 6; vehicle->bus->busType->busvendor->wheels = &wheel; vehicle->bus->busType->busvendor->seats = 60; } } int main(int argc, char *argv[]) { Vehicle myvehicle; fillDetails(&myvehicle, 0); //get car details filled & retrieve the details as "Maker" struct Maker *maker; maker = (Maker *) malloc(sizeof(Maker)); maker = myvehicle.car->carType; printf("Name of car =%s", maker->carvendor->name); return 0; </code></pre> }
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pointers to structs inside union: how to initialize and retrieve struc values
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