Can't create or write a .txt file in C - c

Question

I'm trying to create and write to a file in C - for whatever reason this code is running successfully however, doesn't create a file. Please find my code below, any help would be appreciated
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
int num;
FILE* fptr;
fptr = fopen("E:\\SAMPLE FILES\sample.txt", "w+");
if (fptr == NULL)
{
printf("Error!");
exit(1);
}
printf("Enter num: ");
(void)scanf("%d", &num);
fprintf(fptr, "%d", num);
fclose(fptr);
return 0;
}

Answer 1

This is a very simple problem.
fptr = fopen("E:\\SAMPLE FILES\sample.txt", "w+");
This is the problem. As you would know, the \ is used to define an escape sequence. Because of that, for an actual \, you have to put it 2 times, like you did at E:\\. The file, instead of creating in SAMPLE FILES, is created at the root directory.
Change it to :
fptr = fopen("E:\\SAMPLE FILES\\sample.txt", "w+");
And your code should work. I tested it an I got output.
Make sure you have a folder named SAMPLE FILES on E: Or else, fopen() returns NULL.

Answer 2

In order to open a file for reading or writing, it is best to at least have some sort of error checking and reporting on it. Please see the basic example below:
#include <stdio.h>
#include <errno.h>
#include <string.h>
extern int errno ;
int main () {
FILE * pf;
int errnum;
pf = fopen ("e:\\sample files\\sample.txt", "wb");
if (pf == NULL) {
errnum = errno;
fprintf(stderr, "Value of errno: %d\n", errno);
perror("Error printed by perror");
fprintf(stderr, "Error opening file: %s\n", strerror( errnum ));
} else {
printf("Enter num: ");
(void)scanf("%d", &num);
fprintf(fptr, "%d", num);
fclose(fptr);
fclose (pf);
}
return 0;
}
At least that way, if you get an error being displayed, you stand a good chance of fixing or dealing with it programmatically.

Answer 3

fptr = fopen("E:\SAMPLE FILES\sample.txt", "w+");
->
fptr = fopen("E:\SAMPLE FILES\sample.txt", "w+");
try