php - why adding this code to my header in Wordpress doesn't activate "allow_mobile_zooming" -

should putting functions.php file load instead? here's code i'm using, allows finger zoom on mobile devices:

function allow_mobile_zooming() { print '<meta name="viewport" content="width=device-width, user-scalable=yes, initial-scale=1.0, minimum-scale=0.1, maximum-scale=10.0">'; print "\n";}  add_action( 'wp_head', 'allow_mobile_zooming', 9999999 ); 

thanks!

if you're adding header.php, can write html , not php:

or add functions.php you've written. code looks correct.

but doesn't make sense add code header.php, since it's doing calling hook add header. , if place code in header.php after wp_head(), won't work wp_head has been called.