Is there a way for a running program to write on a txt file

Question

Is there a way for a program to write to a txt file while running? I've created a simple program that can write to a text file using fprintf() but I can only view the written data after the program has been terminated? Is there a way for it to write simultaneously? For simplicity, assume variables and functions declared.

My code goes something like this:

typedef char STRING50[51];
STRING50 sentence;

do {
TransferToText(sentence); // so that after the encode, it goes back here to write to the text file.

showChoices(); //show choices
// A. Write to a txt file
// B. Exit
// CHOICE:
fflush(stdin);
scanf(" %c, &cChoice);

switch (cChoice) {
    case 'A':
    case 'a':
        Encode(sentence); // a function that asks the user to input to a string.
        tryAgain = 1;
        break;
    case 'B':
    case 'b':
        tryAgain = 0;
        break;
    default:
        tryAgain = 1;
        break;
}

} while (tryAgain == 1);

I run the program, after entering an input for the Encode() function, I expect that it should have written to the txt file already but, it's blank. Only if I terminate the program does it show.

If you have a suggested code also for the program in general not just the answer, please educate me.

Answer 1

You can flush after every file operation like see sample code below

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

int main()
{
    int i=0;
    FILE *fptr;
    char word[100];

    fptr=fopen("out.txt","w");

    if(fptr==NULL)
    {
        printf("File Error");
        exit(1);
    }

    for(i=0;i<100;i++)
    {
        fgets(word,100,stdin);
        word[strlen(word)-1]='\0';
        fprintf(fptr,"%s\n",word);
        fflush(fptr);
    }

    return 0;
}

and in your code fflush(stdin); fflush is not for input stream

Answer 2

Probably an fclose after writing will help. (If you want to write data again to the file, this is not a solution - thanks for the comment)