There are 2 meanings of "header":
HTML headers ()
HTTP headers.
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This is simple, (from viewpt of PHP programming)
Clients don't send HTML so don't send headers.
PHP server sends it to a client browser as part of HTML text, either simple
text or php-echo.
PHP acting as client to another server (myfetch), receives it as part of the
text; and can extract it. E.g. I extract BASE from the header.
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HTTP headers
There are 4 cases, generated by {send, receive} and acting as {client, server}
1) myphp receives cookies from a client browser, with the call that activated
the PHP page.
$_COOKIES[]
2) myphp sends cookies to a client browser.
Must set header before first char of page is emitted.
3) myphp receives cookies as a client to another server (myfetch).
Need to get at the hidden HTTP header received.
4) myphp sends cookies as a client to another server (myfetch).
Create cookies as part of:
one (or more) lines, (terminated by CRLF)
inside the "header" part,
of the args used by http_build_query();
building a "context"; (stream_context_create($opts);)
before (used in) the call (of file_get_contents() )
See "myfilegetcontents" file for code.