Strangely enough, in the player.log file you can find the following lines after the LOG_test file presents itself.
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hullo
(Filename: C:\buildslave\unity\build\Runtime/Export/Debug/Debug.bindings.h Line: 48)
Path: C:\Users\<yourUsername>\Desktop\LOG_test_date_12-12-87.txt
(Filename: C:\buildslave\unity\build\Runtime/Export/Debug/Debug.bindings.h Line: 48)
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Likely, just evidence of the file being created but,
Hullo to you too John