On UNIX and Linux platforms, you can stop the database server using the stop_iq utility.
Use stop_iq to stop your server and close all user connections to your server.
stop_iq shuts down a server without regard for user connections or load process status. Normally, do not shut down a server while it is still connected to one or more clients.
The dbstop utility offers a finer level of control, providing options to control whether a server is stopped based on user connections.
For full details on when to use stop_iq, see System Administration Guide: Volume 1 > Sybase IQ Startup > Database Server Shutdown.