Memory error, access violation.
- by Ordo
Hello! I'm learning C on my own and as a exercise i have written a program but it does not work. The program is splitted into 3 parts. A header file, a main file for executing the program a file to define the functions. I'm not using all the functions yet but that shouldn't be the problem.
Here is my header file, nothing special in it.
#ifndef EMPLOYEE_H
#define EMPLOYEE_H
struct Employee
{
char first[21];
char last[21];
char title[21];
int salary;
};
struct Employee* createEmployee(char*, char*, char*, int); // Creates a struct Employee object on the heap.
char* getfirstname (struct Employee*);
char* getlastname (struct Employee*);
char* gettitle (struct Employee*);
int getsalary (struct Employee*);
void setfirstname (struct Employee*, char*);
void setlastname (struct Employee*, char*);
void settitle (struct Employee*, char*);
void setsalary (struct Employee*, int);
void printEmployee(struct Employee*);
#endif
In this file i define the functions and how they work:
#include "7.1.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Employee* createEmployee(char* first, char* last, char* title, int salary) // Creates a struct Employee object on the heap.
{
struct Employee* p = (struct Employee*) malloc(sizeof(struct Employee));
if (p != NULL)
{
strcpy(p->first, first);
strcpy(p->last, last);
strcpy(p->title, title);
p->salary, salary;
}
return p;
}
char* getfirstname (struct Employee* p)
{
if (p != NULL)
return p ? p->first : "";
}
char* getlastname (struct Employee* p)
{
if (p != NULL)
return p ? p->last : "";
}
char* gettitle (struct Employee* p)
{
if (p != NULL)
return p ? p->title : "";
}
int getsalary (struct Employee* p)
{
if (p != NULL)
return p ? p->salary : 0;
}
void setfirstname (struct Employee* p, char* first)
{
if (p != NULL)
strcpy(p->first, first);
}
void setlastname (struct Employee* p, char* last)
{
if (p != NULL)
strcpy(p->last, last);
}
void settitle (struct Employee* p, char* title)
{
if (p != NULL)
strcpy(p->title, title);
}
void setsalary (struct Employee* p, char* salary)
{
if (p != NULL)
p->salary, salary;
}
void printEmployee(struct Employee* p)
{
if (p != NULL)
{
printf("%s, %s, %s, %d",
p->first,
p->last,
p->salary,
p->salary
);
}
}
And the last file is used to executed the program/functions:
#include "7.1.h"
#include <stdio.h>
#include <stdlib.h>
int main ()
{
char decision;
struct Employee emp;
struct Employee* emps[3];
for ( int i = 0; i < 1; i ++)
{
printf("Please type in the emplooyes data.\nFirstname:");
scanf("%s", emp.first);
printf("Lastname:");
scanf("%s", emp.last);
printf("Title:");
scanf("%s", emp.title);
printf("Salary:");
scanf("%d", &emp.salary);
emps[i] = createEmployee(emp.first, emp.last, emp.title, emp.salary);
}
printf("Do you want to print out your information? (Y/N):");
scanf("%c", &decision);
if (decision == 'y' || decision == 'Y')
{
printEmployee(emps[1]);
}
}
I don't know what the problem is. I 'm always getting the following error message after typing in first, last, title and salary for the first time. The error is written in german. It means:
Unhandled exception at 0x102de42e (msvcr100d.dll) in 7.1.exe: 0xC0000005: Access violation when writing to 0xCCCCCCCC position.
I could fix the first problem with the hints given below. Now when i want to print out the employee data using the function:printEmployee(emps[1]);, I get the same kind of error with access violation.
