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cstructsegmentation-faultfgets

Trying to read data from a text file, make a struct from it, and print the fields to stdout


I seem to have no problems reading from the file and then creating the struct, but printing the struct gives me a segmentation fault.

Employee definition

struct _Employee {
  int salary; // Monthly salary in UK pounds sterling
  char *name; // Pointer to character string holding name of employee.
  char* department;           // MUST be dynamically allocated from the heap.
};

typedef struct _Employee Employee;

Function to read from a file

Employee* readfile(FILE* file) {
  Employee* newemployee;
  newemployee = malloc(sizeof(Employee));
  char tempsalary[10];
  int salary;
  char name[20];
  char dept[20];
  char* names = malloc(sizeof(name));
  char* depts = malloc(sizeof(dept));
  char* status; // Returned by fgets(). Will be NULL at EOF


    status = fgets(names, sizeof(name), file);
    if (status == NULL)
      return NULL;
    else {
      newemployee->name = strdup(status);


    fgets(tempsalary, sizeof(name), file);
    sscanf(tempsalary, "%d", &salary);
    newemployee->salary = salary;

    fgets(depts, sizeof(dept), file);
    newemployee->department = strdup(depts);

    return newemployee;
    }
}

Function to print the struct generated by readfile.

void printEmployee(Employee *employee) {
      fprintf(stdout, "Name = %sSalary = %d\nDepartment = %s\n\n", // SEGFAULT HERE
          employee->name, employee->salary, employee->department);
}

Main program

int main() {
  FILE* file;
  file = fopen ("stest2.txt", "r");
  Employee* employees[max_employees];
  int i;
  int c;
  Employee* temp;

    for (i = 0; i < max_employees; i++) {
    employees[i] = readfile(file)   
    printEmployee(employees[i]);
    }
  return 0;
}

Solution

  • readfile() can return NULL in case of fgets error. This case is not handled in main. As a primitive suggestion:

        for (i = 0; i < max_employees; i++) {
            employees[i] = readfile(file);
            if(NULL != employees[i])
            {   
                printEmployee(employees[i]);
            }
            else
            {
                printf("Error reading file");
            }