How to check if a user is already logged?

Quevas

As topic...
I should use a log file to store users, but is it possible without using files?

ednark

the concept is to use a [man]session[/man]....

this by default however, uses a file to store the session... but you can always override it to use your favorite database...

Quevas

Could you post an example please?
Thanks.

ednark

wait... you are asking where to store users?

you are asking for a database to use.

You should look into a Relational Database to store users.

you described using a flat file database, ok for small numbers of users, but takes a lot of effort to pull infromation out of them.

Postgres and Mysql are the two big free ones..

you use SQL to ask these databases questions...

read more on how sql queries to a database work here:
http://www.w3schools.com/sql/default.asp

i mean that you use a session to keep your webpage informed as to which user is logged in at the moment.

Quevas

Thanks, but my request was on how to use sessions in this case.
I was not much clear, sorry.

What I need is the same username can't be logged at the same time.
I hope I'd been more clear.

ednark

you would have to find a place that exists to all users logged in.... (ie your database)
and make a

USERS_LOGGED_IN_RIGHT_NOW
--- userid
--- ip_address
--- login_time

table

when a user tries to log in onthe site

it verifies their username and password...

if they are both ok then you look for an entry in the table

if it exists... you see if there is an entry in your table

if there is you print out

sorry, you already logged in from ip_addr at login_time

however you run into problems this way...

you have to be assured that the server itself will forget about the session the moment the user closes the browser or loggs off... this in itself is a problem...

Quevas

Ok, I'll try in this way. Thanks 🙂