How can the problem of only one function (htmlspecialchars or nl2br) being executed be resolved in PHP?

The issue of only one function being executed can be resolved by chaining the functions together. This means passing the output of one function as the input to the next function. In this case, we can first apply htmlspecialchars to escape special characters, and then apply nl2br to convert newlines to HTML line breaks.

$text = "Hello, <b>world</b>!\nHow are you?";
$output = nl2br(htmlspecialchars($text));
echo $output;