SECNDS — Time function ¶SECNDS(X) gets the time in seconds from the real-time system clock.
X is a reference time, also in seconds. If this is zero, the time in
seconds from midnight is returned. This function is non-standard and its
use is discouraged.
GNU extension
Function
RESULT = SECNDS (X)
| T | Shall be of type REAL(4). | 
| X | Shall be of type REAL(4). | 
None
program test_secnds
    integer :: i
    real(4) :: t1, t2
    print *, secnds (0.0)   ! seconds since midnight
    t1 = secnds (0.0)       ! reference time
    do i = 1, 10000000      ! do something
    end do
    t2 = secnds (t1)        ! elapsed time
    print *, "Something took ", t2, " seconds."
end program test_secnds