How to get file path when using MOD PLSQL

CREATE OR REPLACE Function GETFILEPATH return varchar2 is script_name varchar2(255) default owa_util.get_cgi_env(‘SCRIPT_NAME’); path_info varchar2(255) default owa_util.get_cgi_env(‘PATH_INFO’); pos number; BEGIN script_name := script_name || path_info; pos := instr(script_name,’docs’); script_name := substr(script_name,pos+5,length(script_name)-pos-4); return script_name; END; /