C Program to read a text file

Program

#include<stdio.h>
#include<stdlib.h>
void main()
{
	FILE *file_ptr;
	int buf;
	file_ptr = fopen("read.txt", "r");
	if(!file_ptr)
	{
		printf("Unable to open file\n");
		exit(0);
	}	
	else
		printf("File open successful\n");
	fclose(file_ptr);
}

Output 1

File open successful

Output 2

Unable to open file