Changed Functions
  
   Several functions were given new, optional parameters in PHP 5.4:
  
  PHP Core:
  
   - 
    
     Added the optional limitparameter to debug_backtrace()
     and debug_print_backtrace(), to limit the amount of stack frames returned.
- 
    
     is_link() now works properly for symbolic links on Windows Vista
     or later. Earlier systems do not support symbolic links.
    
   
- 
    
     parse_url() now recognizes the host when a scheme is omitted, 
     and a leading component separator is present. As of PHP 5.4.7.
    
   
OpenSSL:
  
  Intl:
  
   - 
    
     idn_to_ascii() and idn_to_utf8() now take two extra
     parameters, one indicating the variant (IDNA 2003 or UTS #46) and another, passed by reference,
     to return details about the operation in case UTS #46 is chosen.