Are any of the windows in your PowerBuilder applications “haunted” by ghosts?
In the Windows operating system, the term “ghosting” is used to describe how the Desktop Window Manager visually intervenes on a user’s behalf whenever Windows believes the active, or "top-level" application window has become unresponsive. This article describes how Windows determines if a window should be ghosted and how the appearance of a window changes when it becomes ghosted. The article will also examine the common causes of an unresponsive PowerBuilder window and discuss some options for detecting, recovering from and even preventing windows with long-running processes from being ghosted.
Let’s start where most things begin… at the beginning – with an overview of the role of messages and message queues in an event-driven operating system.