If you are working with Sybase Central, you can keep track of all users connected to the database. You can view properties of these connected users, and you can disconnect them if you want.
Select the database in the left pane, and click the Connected Users tab in the right pane.
This tab displays all users currently connected to a given database (including yourself), regardless of the application that they used to connect (Sybase Central, Interactive SQL, a custom client application, and so on).
Select the database in the left pane, and click the Connected Users tab in the right pane.
Select the desired user and then choose File > Properties.
Inspect the desired properties.
Select the database in the left pane, and click the Connected Users tab in the right pane.
Select the desired user and then choose File > Disconnect.