Bir metin dosyasından dize Okuma bir ikili arama ağacı oluşturmak

İşte benim kod şimdiye kadar olduğu

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

#define lineSize 256

struct recordNode {
   char district[256];
   int employees;
   int employers;
   int students;
   int retried;
   int others;
   struct recordNode* left;
   struct recordNode* right;
};

struct stockNode* addRecord(struct recordNode* tree, struct recordNode node) {
   struct recordNode* newnode;
   struct recordNode* searcher;

   /* allocate memory block and assign parameter values to it */
   newnode = (struct recordNode*)malloc(sizeof(struct recordNode));

   newnode->left = NULL;
   newnode->right = NULL;
   /* check if the tree is empty, and in such case, return the newnode as*/
   /* the first node of the tree */
   if (tree == NULL)
     return newnode;
   /* searcher is the pointer to search for the correct location for insertion */
     searcher = tree;
   while (1) {
   /* see if the newnode should go to left branch */
      //if (code < searcher->code) {
      if (strcmp(tree->district, node.district) < 0) {
      /* yes, and if the left branch is empty, this is the insertion location */
         if (searcher->left == NULL) {
            searcher->left = newnode;
            return tree;
         }
      else { /* not yet, keep moving to the next level down */
         searcher = searcher->left;
         continue;
      }
   }
   /* see if the newnode should go to right branch */
      if (strcmp(tree->district, node.district) > 0) {
   /* yes, and if the right branch is empty, this is the insertion location */
         if (searcher->right == NULL) {
            searcher->right = newnode;
            return tree;
         }
      else { /* not yet, keep moving to the next level down */
        searcher = searcher->right;
        continue;
      }
   }
   else {
      free(newnode);
      return NULL; /* an error indication */
   }
   }
}

void getFile () {
   struct recordNode node;
   struct recordNode *tree;

   FILE* fpin;
   FILE* fpout;

   char line_buffer[lineSize]; /* BUFSIZ is defined if you include stdio.h */
   int counter = 0;

   //file validation
   fpin=fopen(testData.txt, r);

   if (fpin == NULL ) exit(0);
        counter = 0;
    while (fgets(line_buffer, sizeof(line_buffer), fpin)) { 
               counter++;
               if (counter != 1) {
               sscanf(line_buffer, %[^','],%d,%d,%d,%d, node.district, &node.employees, &node.students, &node.retried, &node.others);
               tree = addRecord(tree, node); **//ERROR**

               }

    }
        getchar();

}

void main() {

   getFile();
   getchar();

}

Aşağıdaki satır:

tree = addRecord(tree, node);

Bu hatayı verir:

// HATA Proje Project2.exe adresinde 32657E39 de iletinin 'Erişim ihlali ile istisna sınıfı EAccessViolation kaldırdı. Adresine 00000001' arasında okuyunuz. Süreç durduruldu. Adım kullanın veya devam etmek için çalıştırın

Bu sorunu nasıl düzeltebilirim?