Write whatever error in log file

Hi all,

I have

export LOG_FILE=$HOME_DIR/error.log
sqlplus -s /nolog << EOF
whenever sqlerror exit sql.sqlcode
@$HOME_DIR/connect.sql
whenever sqlerror exit sql.sqlcode 
@$SQL_FILE
EOF

can display the sql error in putty, how can I write them into log file ?

Do

sqlplus -s /nolog << EOF
spool error.log
whenever sqlerror exit sql.sqlcode
@$HOME_DIR/connect.sql
whenever sqlerror exit sql.sqlcode 
@$SQL_FILE
spool off;
EOF

Thanks