Thread: Passing a dynamic array to a function

Hello!
I'm having some problems with dynamic arrays passed by reference.
I have an add_employee() function which receives a pointer to a dynamic array of Employee structures.
The purpose of this function is to add employees to an array, everytime this function is callled and reallocate the size of the array to accomodate new employees.
The problem is I'm given an "Unhandled Exception" each time the function is called for the second time(to add a second employee to the array).The first time it works alright and the array is filled with the information passed on the call to gets();
Here's the Employee function:

Code:

int add_employee(Employee **employee,int n_employees)
{
	
	
	n_employees++;

	*employee=(Employee*) realloc(*employee,n_employees* sizeof(Employee));
	
 
	if(*employee== NULL)
	{
		fprintf(stderr, "Error alocating memory!");
		exit(1);
	}
	

	printf("Introduce employee name:\n");
	fflush(stdin);
	gets(employee[n_employees-1]->name);
	employee[n_employees-1]->id=n_employees;
	
	
	return n_employees;
}

If I use this code directly in main it works alright,but in this function it doesn't.
What could I be doing wrong?

Is it C ?? unhandled exception?
Post how you call function,pass parameter,etc.

Yes,it's C.
Here it is the main function:

Code:

void main()
{
        int n_employees=0;
	Employee *emp=NULL;

	.........
		
	emp=(Employee *)malloc(sizeof(Employee));

		if(emp==NULL)
		{
			fprintf(stderr,"Error alocating memory!"); 
			exit (1); 
		}
			

   
    do{
       ...
  
            case 2: 		
				do
				{
					...
					switch(opsub)
					{
						case 1:
					n_employees=add_employee(&emp,n_employees);
                                                break;
                                         ...
                                        }
                                } while(opsub!=5);
							
           }while(op!=5);

is name field in Employee array ?? How is Employee defined ?
Use fgets() rather than gets().
fflush(stdin)
c-faq

The Employee structure in Employee.h:

Code:

typedef struct employee
{
    char name[100];
    int id;

}Employee;


int add_employee(Employee **employee,int n_employees);

Can't you simplify this? say like :

Code:

int add_employee(Employee **employee,int n_employees)

int main(void)
{
   int i;
   int n = 0;
   Employee *emp  = NULL;
   for(i = 0; i < 5; i++) {
      n = add_employee(&emp,n);
   }

  return 0;
}

Unfortunately, no as the number of employees is undefined and that for cycle would limit the call to the function add_employee to 5 times.

You are not getting what i meant. It's to isolate your add_employee function. I guess the problem is somewhere else.

Originally Posted by Bayint Naung

You are not getting what i meant. It's to isolate your add_employee function. I guess the problem is somewhere else.

I've tried what you said,isolating it,but the "Unhandled Exception...Access Violaton" persists and it only appears when i try to add a second employee...The line of code where it breaks for the second time is gets(employee[n_employees-1]->name); and the value i see on Visual studio is some hexadecimal with <Bad Ptr> writen
The strange thing is that the 1st time it works just fine!

Code:

	gets( (*employee)[n_employees-1].name);
	(*employee)[n_employees-1].id=n_employees

;

Originally Posted by Bayint Naung

Code:

	gets( (*employee)[n_employees-1].name);
	(*employee)[n_employees-1].id=n_employees

;

Thank you!I was struggling with that for a long time!
Just one last question: if I wanted to print the contents of each array,how would it look like?Currently I have:

Code:

for(i=0;i<n_employees;i++)
	{
	printf("Name: %s\n",*(*(employee[i].name)));
	printf("ID: %d\n",*(*employee)[i].id);
	}

Unfortunately this doesn't work..

Is it complete function?

You are on YOUR OWN now. :P