5 calls to drupal_get_http_header()

ajax_deliver in includes/ajax.inc
Packages and sends the result of a page callback as an Ajax response.
drupal_deliver_html_page in includes/common.inc
Packages and sends the result of a page callback to the browser as HTML.
drupal_page_set_cache in includes/common.inc
Stores the current page in the cache.
drupal_send_headers in includes/bootstrap.inc
Sends the HTTP response headers that were previously set, adding defaults.
drupal_serve_page_from_cache in includes/bootstrap.inc
Sets HTTP headers in preparation for a cached page response.

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