[ferret_users] Embed ferret in Fortran program

[Haoguo Hu <haoguo.hu@xxxxxxxx>]

Dear Ferret-eers,

I try to embed Ferret in Fortran program,

!--begin Fortran program----------
do istep=1,9000
   -------
   call system("ferret -nojnl -script plot.jnl")
enddo
!--end Fortran program----------


plot.jnl
!--begin plot.jnl----------
  use "eco.nc"
  fill/k=1/L=1 tem         !temperature
  spawn sleep 2s
!--end plot.jnl----------


The question is:
1. How can I make the L=istep happen?
2. How to let the Ferret window open only once and the plotting keep 
going with the "istep"?


Thanks


HH