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cookies are persistence?

kri shan
Ranch Hand

Joined: Apr 08, 2004
Posts: 1432
Whether cookies are persistence? because cookies are stored in the local disk.
Eric Pascarello

Joined: Nov 08, 2001
Posts: 15385
They are persistent on that machine if the expire attribute is set. They are not persistent if you need that information and the user logs on another machine.

Is that what you are after?
David O'Meara

Joined: Mar 06, 2001
Posts: 13459

The quick answer is "Yes, sort of".

Firstly there are two types, persistent and session cookies. The persistent type get written to the filesystem, the session ones get destroyed when you close the browser.

It is poor form to use them as a type of persistence though. Firstly they can be blocked by many browsers or deleted by users, so you can't rely on them. They are also accessible by the user, so the user can read the data and potentially change it.

Consider a simple case where someone logs into your system and to prevent them having to log in again, you write their user ID to their local file system as a cookie. By changing the cookie value, the user now has the ability to log in as anyone they like.
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subject: cookies are persistence?
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