"prefer open position settings" in engines

[kaustubh]

The engines like shredder have setting called "prefer open position " , i want to ask you how does it work in programming. Like should we check the pawn structure and decide whether it is closed or open position or should we see if we are not getting open files after some ply .

[YL84]

Hi,
apart the pawn structure and open files you mentioned, there is also the possibility of playing with "mobility" terms.
But usually, an open position is reached after 1. e4 so that if you wan't open positions plays 1.e4 with white (avoid other moves like 1.d4 1.c4 1.Nf3). Of course it is a coarse grain rule. So there is maybe some possibilities to change the opening book (or avoid some lines) according to the settings.
Yves

[bob]

The engines like shredder have setting called "prefer open position " , i want to ask you how does it work in programming. Like should we check the pawn structure and decide whether it is closed or open position or should we see if we are not getting open files after some ply .

It is almost certainly a coefficient that multiplies the static analysis for pawn mobility by some fraction. This would include things like pawn rams, pawns that can't possibly advance without being captured by an enemy pawn that would be protected after capturing, etc...