[gmx-users] how to write in a script?

[Albert]

Hello:

I am trying to make a workflow of system building steps of gromacs. 
However, many steps require interactive input such as:

genion, make_ndx

the genion can be done with echo:

echo 15| ${genion} -s Complex_b4ion.tpr

However, when I try to run:

echo 1|14 make_ndx -f input.pdb

However, it doesn't work for the above command.

Does anybody have any idea how can we write make_ndx in a script?

thx a lot

Albert