>exist only one difference on the temporaly files that i'm talking about, my files are "dbf's"....so these files can be open it with the command "fopen"?

If you have files with a DBF extension that were created using SQL Select then they are not temporary. Are you using SELECT ... INTO TABLE MyTempCursor or are you using SELECT ... INTO CURSOR MyTempCursor. The second creates temporary files that go away when closed; the first does not.

And yes you can open any file with any extension using FOpen(). You won't be able to read the records but you can open the file.