Add header_register_callback(), allows a userland function

to be called as all the headers are being sent and after all
of the default headers have been merged.

headers_list(), header_remove() and header() can all be used
inside the callback.

<?php

header('Content-Type: text/plain');
header('X-Test: foo');

function foo() {
  foreach (headers_list() as $header) {
    if (strpos($header, 'X-Powered') !== false) {
      header_remove('X-Powered-By');
    }
    header_remove('X-Test');
  }
}

$result = header_register_callback('foo');
echo "a";

1 files changed, 3 insertions, 0 deletions

diff --git a/NEWS b/NEWS
index 8ab552fcb8..898b701b79 100644
--- a/NEWS
+++ b/NEWS
@@ -42,6 +42,9 @@ PHP                                                                        NEWS
   . Added support for object references in recursive serialize() calls.
     FR #36424. (Mike)
   . Added http_response_code() function. FR #52555. (Paul Dragoonis, Kalle)
+  . Added header_register_callback() which is invoked immediately
+    prior to the sending of headers and after default headers have
+    been added. (Scott)
   . Added DTrace support. (David Soria Parra)
   . Improved output layer, see README.NEW-OUTPUT-API for internals. (Mike)
   . Improved unserialize() performance.