You want to print the execution plan only?
Recent versions of SQL*Plus, SQL Dev, etc. have the set feed only option. This suppresses the rows, but shows the row count.
To get the plan you'll want to call DBMS_Xplan in some way:
set serveroutput off
set echo off
set feed only
set timing on
cl scr
spool c:\temp\out.log
select * from dual;
set feed on
select *
from table(dbms_xplan.display_cursor(null, null, 'BASIC LAST'));
spool off
Spools this to the file:
1 row selected.
Elapsed: 00:00:00.268
PLAN_TABLE_OUTPUT
EXPLAINED SQL STATEMENT:
------------------------
select * from dual
Plan hash value: 272002086
----------------------------------
| Id | Operation | Name |
----------------------------------
| 0 | SELECT STATEMENT | |
| 1 | TABLE ACCESS FULL| DUAL |
----------------------------------
13 rows selected.
Elapsed: 00:00:00.414