A parent session can stop a child session by using DosStopSession. Stopping the child session ends the processes in that session. It also stops any sessions related to the child session. If a child session is in the foreground when it is stopped, the parent session becomes the foreground session. DosStopSession breaks any bond that exists between the parent session and the specified child session.

A process running in the session specified in the call to DosStopSession can ignore the request to end. If this happens, DosStopSession still returns 0 (indicating success). The only way to be certain that the child session has ended is to wait for notification through the termination queue specified in the call to DosStartSession. OS/2 writes a data element into the specified queue when the child session ends. The process in the parent session must call DosReadQueue to retrieve this data element, which contains the session identifier for the child session and the return value for the process in the child session. Only the process that created the child session can read the data element.