Bibtex, bst and authors names

To get only initials in authors names (Bibtex), I change this line in
FUNCTION {format.names}:

 { s nameptr "{ff~}{vv~}{ll}{, jj}" format.name$ 't :=

for

 { s nameptr "{f{.}.~}{vv~}{ll}{, jj}" format.name$ 't :=