Provide FME with a callback function that will be called whenever a message is logged. By default, messages will be logged to both the callback function and the Log file. If setFileName is called with None as the filename parameter, then messages will only be sent to the callback.

The callback function must take two arguments: An int severity, and a str message.


function (Callable) – The function to provide FME for use as a callback function.

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