Extended Predicates

There are a number of predicates that appear as built-ins to the system but are really extended predicates that are environment specific. For Windows environments these are implemented in a Logic Server Extension DLL (LSX) A4WIN.LSX. Examples of environment-specific extended predicates are chdir/1 (change directory) and findfiles/3 (find file names in a directory structure). These are described under Extended Predicates in the Prolog User's Guide.

The Amzi! IDE and the Amzi! command line tools are all Logic Server applications. They automatically load A4WIN.LSX as part of Logic Server initialization. This is why it appears as if predicates like chdir/2 and findfiles/3 are part of the system. If you want to use these predicates in your own stand-alone applications, you must either implement the extended predicates in your application or load A4WIN.LSX with your application.

The full source code for A4WIN.CPP is included in directory SOURCE\LSX\AWIN.