Member variable Error():thread Foundation
Contains the ID number of the thread in which an error occurred.
The operating system provides multi-threading, by which different parts within a single application are able to run simultaneously. These parts are executed independently of each other in threads. A thread is assigned a numerical code by the operating system and this numerical ID is contained in the instance variable :thread. It gives information about the thread in which the error occurred. Normally the value is equal to 1, which is the ID for the thread in which an application is started. If an error occurs in a thread other than the main thread, this instance variable contains a value not equal to 1.
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