The stpncpy function copies at most n characters from the string
pointed to by src, including the terminating '\0' character, to the
array pointed to by dest. Exactly n characters are written at
dest. If the length strlen(src) is smaller than n, the
remaining characters in the array pointed to by dest are filled with
'\0' characters. If the length strlen(src) is greater or equal to
n, the string pointed to by dest will not be '\0' terminated.
The strings may not overlap.
The programmer must ensure that there is room for at least n characters