will PHP header() & exit() securely terminate a script before redirecting? -

Is a user only a safe way to protect the area?

  if (! Isset ($ _ session ['username'])) {redirect (SITE_ROOT. 'St_pages / login /');}  

Using:

function redirect ($ url) {header ('location:'. $ Url); Exit ('& lt; a href =' '. $ Url.' "& Gt; To redirect you: '. $ Url.' & Lt; / a & gt; ');}

Yes it is safe

Although the header () does not end anything, but Exit () actually eliminates a script; this is the only purpose of this function