Cookie exchange between subdomains?

Question

HTTP Cookies

Can a api.example.comcookie be sent to dev.example.com? That is, is it possible to exchange cookies between subdomains?

Answer 1

no
But you can make a cookie in a domain
and the cookie will be visible in both domains

Answer 2

Cookies can only be set on a domain and its subdomains.
Accordingly, globally there are exactly 2 options to make a cross-domain cookie:
a) on the domain, example.comput a handler that hangs the cookie on the desired domain dev.example.comor .example.com
b) on the domain, dev.example.comput the handler that hangs the cookie on the same domain.
You can do it in php, you can (although not securely) do it through js (for example , liba ) - but in any case, you need access to either the target domain or the top-level domain.

Answer 3

Can api.example.com send a Cookie to dev.example.com? That is, is it possible to exchange cookies between subdomains?

Why is this impossible? Maybe! Domain 1 example.com !!! So you can link all its subdomains.
If puffed, then in php.ini:
but as noted above, the cookie must be created from example.com. This is problem?