mh-lpr-command-format

mh-lpr-command-format is a variable defined in `mh-e.el'.
Its value is

"lpr -J '%s'"

Documentation:
*Command used to print.

This option contains the Unix command line which performs the
actual printing for the P l command. The string can
contain one escape, "%s", which is replaced by the name of the
folder and the message number and is useful for print job names.
I use "mpage -h'%s' -b Letter -H1of -mlrtb -P" which produces a
nice header and adds a bit of margin so the text fits within my
printer's margins.

This options is not used by the commands P p or
P f.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 6.0 of the MH-E package that is part of Emacs 22.1.