how to write / in c code example

Example 1: c write to file

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

int main() {
    char sentence[1000];

    // creating file pointer to work with files
    FILE *fptr;

    // opening file in writing mode
    fptr = fopen("program.txt", "w");

    // exiting program 
    if (fptr == NULL) {
        printf("Error!");
        exit(1);
    }
    printf("Enter a sentence:\n");
    fgets(sentence, sizeof(sentence), stdin);
    fprintf(fptr, "%s", sentence);
    fclose(fptr);
    return 0;
}

Example 2: write in a file using c

#include<stdio.h>
int main(){
	FILE *out=fopen("name_of_file.txt","w");
	fputs("Hello File",out);
	fclose(out);
	return 0;
}