Hi Ram,
Welcome to world of SCN 
Please do a search in SCN before posting a question. SCN itself is a big repository where almost every solutions you will get.
please try the program name :rs_abap_source_scan
Please execute the program give Z* or Y* for the programs.Put your search string "priority code" on the string tab and click on exceute .It will display you all possible programs where the mentioned string was used.Please let me know is that what you were looking for.if not please explain your requirement.
Regards,
Kannan