On 2014-07-02 15:04, Reindl Harald wrote:

Am 02.07.2014 16:01, schrieb ihab:

...

i using roundcube with dovecot, i have a question if there is possible to know the number of users that using the mail system (in other word
the online users)

no - how do you imagine that?

• roundcube is a web-application
• HTTP is stateless
• so there are no permanent connections

It is possible as Roundcube does have its own session management, which you could maybe hook into.