Many string or integer options are easy to modify using M-x
customize-option. For example, to modify the option that controls
printing, you would run M-x customize-option RET
mh-lpr-command-format RET. In the buffer that appears, modify
the string to the right of the variable. For example, you may change
the lpr command with ‘nenscript -G -r -2 -i'%s'’. Then
use the ‘State’ combo box and select ‘Save for Future
Sessions’. To read more about mh-lpr-command-format, see
Printing Your Mail.
Options can also hold boolean values. In Emacs Lisp, the boolean
values are nil, which means false, and t, which means
true. The customize-option function makes it easy to change
boolean values; simply click on the toggle button in the customize
buffer to switch between ‘on’ (t) and ‘off’
(nil). For example, try setting mh-bury-show-buffer-flag
to ‘off’ to keep the MH-Show buffer at the top of the buffer
stack. Use the ‘State’ combo box and choose ‘Set for Current
Session’ to see how the option affects the show buffer. Then choose
the ‘Erase Customization’ menu item to reset the option to the
default, which places the MH-Show buffer at the bottom of the buffer
stack.
The text usually says to turn on an option by setting it to a
non-nil value, because sometimes values other than
‘on’ are meaningful. An example of this is the variable
mh-mhl-format-file (see Viewing Your Mail). Other options, such as
hooks, involve a little more Emacs Lisp programming expertise.
You can browse all of the MH-E options with the customize-group
function. Try entering M-x customize-group RET mh
RET to view the top-level options as well as buttons for all of
the MH-E customization groups. Another way to view the MH-E
customization group is to use M-x mh-customize RET.