Step by Step solution about How to resolve the algorithm Read a file character by character/UTF8 step by step in the C programming language

This source code in C programming language reads a text file containing wide characters and prints them on the standard output. In particular it reads the file input.txt and prints its content. It first sets the locale to UTF-8, if the native locale doesn't use it, to ensure that the wide characters are handled correctly. Then it opens the file input.txt for reading. The function fgetwc is used to read a wide character from the file, and putwchar is used to print it on the standard output. The loop continues until the end of the file is reached, which is indicated by the return value WEOF from fgetwc.

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

int main(void)
{
    /* If your native locale doesn't use UTF-8 encoding 
     * you need to replace the empty string with a
     * locale like "en_US.utf8"
     */
    char *locale = setlocale(LC_ALL, "");
    FILE *in = fopen("input.txt", "r");

    wint_t c;
    while ((c = fgetwc(in)) != WEOF)
        putwchar(c);
    fclose(in);

    return EXIT_SUCCESS;
}