Thread: dynamic array and structure problem

Hi all,

I have been trying to make a program to test pointers and structures amongst other things. I have tried to reduce it to the minimal expression because this is where the problem is. The code consists on a structure, three functions (one of which is just a menu).

The two important functions are

employee create();
print_employee();

The objective now is to create an dynamic array of employees and then output the information for a particular employee which I choose by pointing to it with a pointer.

All works fine including memory allocation except that when I, for example, choose to enter two employee records and then later I want to output employee id number one, I still get the output for the last employee entered, that is, the output for employee number two. I think there is something wrong either with the variables I call or with the pointers.

Can anybody hep? code below...

Thank you,

bluetxxth

Code:

#include <stdio.h>
#include <stdlib.h>

//Structure - can I not bury this inside the a function? how to access it later...?
typedef struct employee {
    int emp_index; //To assign a value to each employee for a later "pointing"
    char name[30];
    char address[100];
    int age;
    float salary;
}employee;


// Takes imput that establishes the size of the staff


int staff_size(int emp_num) {

    printf("What is the size of your staff?: ");
    scanf("%d", &emp_num);

    return emp_num;
}

//Takes empoyee data input from user
 employee_create(int emp_num, employee *emp_rec, employee **emp_id) {

    
    printf("\nEnter employee id: ");
    scanf("%d", &emp_rec[emp_num].emp_index);
    printf("\nEnter the name of the employee: ");
    scanf("%s",emp_rec[emp_num].name);
    printf("\nEnter the address of the employee: ");
    scanf("%s", emp_rec[emp_num].address);
    printf("\nEnter the age of the employee: ");
    scanf("%d", &emp_rec[emp_num].age);
    printf("\nEnter the salary of the employee: ");
    scanf("%f", &emp_rec[emp_num].salary);

    //this is an array of id which takes emp_index as the index which in turn is a pointer which has a pointer with an index as its index and which accesses the emp_index value
    emp_id[emp_rec[emp_num].emp_index] = &emp_rec[emp_num];
    
}


void print_employee(employee **emp_id , int emp_num) {
    printf("Enter employee you want to inspect: ");
    scanf("%d",&emp_num);
    printf("\nEmployee summary: Id: %d \nName: %s \nAddress: %s \nAge: %d \nSalary: %f", emp_id[emp_num]-> emp_index, emp_id[emp_num]->name, emp_id[emp_num]->address, emp_id[emp_num]->age, emp_id[emp_num]->salary);//Prints desired employee

}


void menu() {

    printf("----------------------------------------\n");
    printf("|Choose amongst the following options: |\n");
    printf("----------------------------------------\n");
    printf("| 1- Enter employee data:              |\n");
    printf("| 2- inspect employees:                |\n");
    printf("----------------------------------------\n\n");
}

int main(void) {

    int d = 0,  emp_num =0, k;
    int option;
    employee *emp_rec;
    employee **emp_id;
    

   employee emp_struct; // Structure declaration


   emp_rec = malloc (sizeof(emp_struct)*emp_num); // dynamic memory allocation for an array of records
   emp_id = malloc (sizeof(emp_struct)*emp_num);// dynamic memory allocation for an array of employee ids


//generate menu
   menu();

    while (option != 0) {

        switch (option) {

            case 1: printf("\nEnter employee data: ");
                     for(d = 0; d < staff_size(emp_num) ; d++){
                      employee_create(emp_num, emp_rec, emp_id);
                      break;
                        }break;

            
            case 2: printf("\nInspect employee: ");
                    print_employee(emp_id, k);
                    break;
                    

        }

        printf("\nSelect an option: ");
        scanf("%d", &option); //Returns to default state

        //exit while loop
    }

   free(emp_rec);
   free(emp_id);

    return (0);
}