/* format: style3 */
clock_speed:
     proc;

dcl       (e1, e2, e3, s1, s2, s3)
                              fixed bin (71);
dcl       (overhead, ext_time, int_time, v)
                              fixed bin (71);
dcl       i                   fixed bin;
dcl       clock               builtin;
dcl       clock_              entry () returns (fixed bin (71));
dcl       time_to_english_    entry (fixed bin (71)) returns (char (*));
dcl       ioa_                entry options (variable);

          s1 = clock ();
          do i = 1 to 1000;
          end;
          e1, s2 = clock ();
          do i = 1 to 1000;
               v = clock_ ();
          end;
          e2, s3 = clock ();
          do i = 1 to 1000;
               v = clock ();
          end;
          e3 = clock ();

          overhead = e1 - s1;
          ext_time = divide (e2 - s2 - overhead, 1000, 71, 0);
          int_time = divide (e3 - s3 - overhead, 1000, 71, 0);

          call ioa_ ("overhead = ^a", time_to_english_ (overhead));
          call ioa_ ("avg clock_() time = ^a", time_to_english_ (ext_time));
          call ioa_ ("avg clock() time = ^a", time_to_english_ (int_time));

     end;