YAILS is split in several files. To run YAILS in its "normal" interface format you need YAP-Prolog as well as those files. An example runnning of YAILS is presented bellow :
ciup1> yap
[ YAP version 3.0 ]
[ Restoring file /usr/local/startup.ys ]
yes
?- [load_yails].
[ consulting load_yails... ]
[ reconsulting il9_main... ]
[ il9_main reconsulted 24804 bytes 0.060 seconds ]
[ reconsulting il9_core... ]
[ il9_core reconsulted 30840 bytes 0.130 seconds ]
[ reconsulting il9_search... ]
[ il9_search reconsulted 35032 bytes 0.180 seconds ]
[ reconsulting il9_classif... ]
[ il9_classif reconsulted 23332 bytes 0.090 seconds ]
[ reconsulting il9_inics... ]
[ il9_inics reconsulted 11376 bytes 0.020 seconds ]
[ reconsulting il9_io... ]
[ il9_io reconsulted 21172 bytes 0.080 seconds ]
[ reconsulting il9_auxs... ]
[ il9_auxs reconsulted 15112 bytes 0.060 seconds ]
[ reconsulting il9_help... ]
[ il9_help reconsulted 15776 bytes 0.030 seconds ]
[ reconsulting il9_tests... ]
[ il9_tests reconsulted 32296 bytes 0.150 seconds ]
[ load_yails consulted 144648 bytes 0.840 seconds ]
?- yails.
===============================================
YAILS - Yet Another Incremental Learning System
===============================================
YAP-Prolog version Mar 1992, Luis
Torgo
YAILS -
From the above figure we can see that three steps are needed before using YAILS :- running YAP-prolog ("yap"); loading YAILS ("[load_yails]."); and runing YAILS ("yails."). After these three steps the prompt of YAILS appears and accepts several commands that can be known executing the command "help.". In order to finish YAILS just execute the command "end.".