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

#define __USE_XOPEN 1

#include <wchar.h>

int   main(void)
{
    setlocale(LC_CTYPE, "en_US.UTF-8");

    wchar_t wch = L'❤';

    printf("%lc %d\n", wch, wcwidth(wch));

    return   0;
}

/*
output:

❤ 1

*/