Run this script :

#! /bin/bash
SID_LIST=`cat /var/opt/oracle/oratab |egrep -v '^(#|$|*)'|cut -f1 -d:`
for sid in $SID_LIST; do
echo " ===== $sid ===== "
su - ora920 -c "export ORACLE_SID=$sid;echo 'select file_name from dba_data_files;'|sqlplus '/ as sysdba'"|egrep '^/'|cut -f5 -d'/'
done