 edit
edit.pl file from the 
commandline (the associated file, see the Prolog flag associated_file 
or the first script file specified using the -s or -l 
command line option. When using the Windows shell while SWI-Prolog is 
associated with the .pl extension this is the file loaded 
by double-clicking a .pl file. See also section 
2.11.1.1.