In the wwwblast package, the programs that perform the actual searches are those with .REAL extesion. The programs are invoked by the corresponding .cgi scripts with the same name. The .cgi in turn is activated by the 'search' button in the corresponding web form contained within the .html page. The .cgi passes the user input from the web form to the .REAL program for processing.
The user inputs encoded within the URL are parsed by .REAL program and used to initiate the actual search. While a search is in progress, the browser - web server connection is maintained by regular ping messages sent from the .REAL program. The final result is displayed in the same browser window when the search is finished.
This workflow requires that the web server be configured to allow the execution of .cgi and .REAL files under the /htdocs/ directory. In addition, TmpGifs directory needs to have appropriate permission settings since overview graphics generated by .REAL programs need to be saved in the this directory.