Function: scroll-bar-mode

Toggle vertical scroll bars on all frames (Scroll Bar mode).
With a prefix argument ARG, enable Scroll Bar mode if ARG is
positive, and disable it otherwise. If called from Lisp, enable
the mode if ARG is omitted or nil.

This command applies to all frames that exist and frames to be
created in the future.

Variable: scroll-bar-mode

Specify whether to have vertical scroll bars, and on which side.
Possible values are nil (no scroll bars), `left' (scroll bars on left)
and `right' (scroll bars on right).
To set this variable in a Lisp program, use `set-scroll-bar-mode'
to make it take real effect.
Setting the variable with a customization buffer also takes effect.