C binary search tree

#include <stdio.h>
#include <stdlib.h>
typedef struct n{

    int data;
    struct node* sol;
    struct node* sag;

}node;

node* tree=NULL;

node* ekle(node* agac,node* yeni){
	if(agac==NULL){
		node* root=(node*)malloc(sizeof(node));
		root->sag=NULL;
		root->sol=NULL;
		root->data=yeni;
	}
	if(agac->data<yeni){
		agac->sag=ekle(agac->sag,yeni);
		return agac;
	}
	agac->sol=ekle(agac->sol,yeni);
	return agac;
}
void dolas(node* agac){
	if(agac==NULL){
		return;
	}
	dolas(agac->sol);
	printf("%d ",agac->data);
	dolas(agac->sag);
}

int main()
{

node* yeni=NULL;
FILE *dosya;
dosya=fopen("veriler.txt","r");
while(feof(dosya)){
	
	fscanf(dosya,"%d",yeni->data);
	ekle(tree,yeni);
	
}
dolas(tree);
    return 0;
}