SUBROUTINE KLINT2(X1, ETA1, X2, ETA2, X0)
 
C  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
C    Returns intersection point in 3-d of two lines.
C
C  X1      real array
C          (x,y,z) of initial point defining line 1
C
C  ETA1    real array
C          direction cosines of line 1 (do not have to be normalized)
C
C  X2      real array
C          (x,y,z) of initial point defining line 2
C
C  ETA2    real array
C          direction cosines of line 2 (do not have to be normalized)
C
C *X0      real array
C          (x,y,z) intersection point. If cannot be determined, it is
C          set to (0,0,0).
C  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>