So, it's not clear to me when the code before any routines gets executed. The error now is: 
% /home/steve/Documents/i_prolog.pl compiled 0.00 sec, 32,784 bytes

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This is not an error, just a message telling you the Prolog module i_prolog.pl has been loaded. If you get it several times it is probably because you are calling set_location_list() repeatedly.

Without seeing the full source code of your application I can only guess, and maybe there are some real bugs on the module annoying you, but it seems to me that the actual problem is that you don't got it yet. You should become more familiar with the module and Prolog and how they work together before trying to use them inside a complex application.

In reply to Re^3: YASWI "Prolog System Error: Thread 1" by salva
in thread YASWI "Prolog System Error: Thread 1" by Steve_BZ

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