groff_mm(7)

Name
groff_mm - memorandum macros for GNU roff

Synopsis
groff -mm [option ...] [file ...]
groff -m mm [option ...] [file ...]

Description
The mm macro package distributed with the groff document formatting system is suitable for the composition of letters, memoranda, reports, and books.

Call an mm macro at the beginning of a document to initialize the package. A simple mm document might use only P for paragraphing. Set numbered and unnumbered section headings with H and HU, respectively. Change the style of the typeface with B, I, and R; you can alternate styles within a word with BI, BR, IB, IR, RB, and RI. Several nestable list types are available via AL, BL, BVL, DL, ML, RL, and VL; each of these begins a list, to which LI adds an item and LE ends the (nested) list. LB begins a list with customizable layout parameters. DS and DF start static and floating displays, respectively; DE terminates either.

groff mm is intended to be compatible with the mm implementation found in the AT&T Documenter's Workbench 3.3 (“DWB”), with the following limitations and changes.

•   Omitted features include the logo and company name strings, }Z and ]S, respectively; the encoded company site location addresses recognized as the third argument to the AU macro; the Pv (“private” heading) register; and the OK (other keywords) and PM (proprietary markings) macros.

•   groff mm implements the CS (output cover page or “sheet”) macro only for memorandum type 4.

•   The grap preprocessor is not explicitly supported; groff mm defines no G1 or G2 macros.

•   Registers A, C, T, and U, set from the troff or nroff command lines with DWB, are not recognized.

•   When setting the registers L or W from the command line, use an explicit scaling unit to avoid surprises.

•   The Le register defaults to 1, consistently with Lf, Lt, and Lx in DWB; equations captioned with EC appear in tables of contents produced by TC.

•   The Li register configures the text indentation of RL list items; DWB used a hard-coded value of 6 ens.

•   groff mm uses the same adjustment and font style defaults in nroff and troff modes.

•   Cut marks are not supported.

DWB supported only seven heading levels. As a compatible extension, groff mm supports fourteen, introducing new registers H8 through H14, and affecting the interpretation of the HF and HP strings.

groff mm features a citation (or “bookmark”) system, permitting the document to make (customizable) internal references like “See chapter 5, page 128.”. Forward references require two-pass formatting. See the INITR macro description below and mmroff(1).

Macro, register, and string descriptions in this page frequently mention each other; most references are to macros. Where a register or string is referenced, its type is explicitly identified. mm's macro names are usually in full capitals; registers and strings tend to have mixed-case names.

Except where noted, mm assumes that horizontal measurements are reckoned in ens (scaling unit n) and vertical ones in vees (scaling unit v). groff mm permits use of non-integral typographical points (scaling unit z). Use explicit scaling units for clarity and predictable behavior.

  Document styles
groff mm offers three frameworks for document organization. COVER/COVEND is a flexible means of preparing any document requiring a cover page. LT/LO aids preparation of typical Anglophone correspondence (business letters, for example). The MT memorandum type mechanism implements a group of formal styles historically used by AT&T Bell Laboratories. Your document can select at most one of these approaches; when used, each disables the others.

  Localization
groff mm is designed to be easily localized. For languages other than English, strings that can appear in output are collected in the file /usr/share/groff/1.24.1/tmac/xx.tmac, where xx is an ISO 639 two-letter language identifier. Localization packages should be loaded after mm; for example, you might format a Swedish mm document with the command “groff -mm -msv”.

This package can also be localized by site or territory; for example, /usr/share/groff/1.24.1/tmac/mse.tmac illustrates how to adapt the output to a national standard using its ISO 3166 territory code. Such a package can define a string that causes a macro file /usr/share/groff/1.24.1/tmac/mm/territory_locale to be loaded at package initialization. If this mechanism is not used, /usr/share/groff/1.24.1/tmac/mm/locale is loaded instead. No diagnostic is produced if these files do not exist.

  Registers and strings
Much mm behavior can be configured by registers and strings. The nr request assigns a value to a register.

    .nr ident [±] n [i]

ident is the name of the register, and n is the value to be assigned. Prefixing n with a plus or minus sign increments or decrements (respectively) its existing value. If assignment of a (possibly) negative n is required, further prefix it with a zero or enclose it in parentheses. If i is specified, the register's value automatically changes by i prior to interpolation if a plus or minus sign is included in the escape sequence as follows.

    \n [±] [ident]

i can be negative; it combines algebraically with the sign in the interpolation escape sequence. The brackets around ident are literal.

Many of the registers mm provides are as Boolean-valued, meaning that they are considered “true” (on, enabled) when they have a positive value, and “false” (off, disabled) otherwise.

Define strings with the ds request.

    .ds ident contents

contents consumes everything up to the end of the line, including trailing spaces. It is a good practice to end contents with a comment escape sequence (\") so that extraneous spaces do not intrude during document maintenance. To include leading spaces in contents, prefix it with a double quote. Interpolate strings with the \* escape sequence.

    \* [ident]

Register and string name spaces are distinct, but strings and macros share a name space. Defining a string with the same name as an mm macro is not supported and may cause incorrect rendering, the emission of diagnostic messages, and an error exit status from troff.

  Register format
A register is interpolated using Arabic numerals if no other format has been assigned to it. Assign a format to a register with the af request.

    .af R c

R is the name of the register, and c is the format. If c is a sequence of Arabic numerals, their quantity defines a zero-padded minimum width for the interpolated register value.

    Form | Sequence
    1 | 0, 1, 2, 3, ..., 10, ...
    001 | 000, 001, 002, 003, ..., 1000, ...
    i | 0, i, ii, iii, iv, ...
    I | 0, I, II, III, IV, ...
    a | 0, a, b, c, ..., z, aa, ab, ...
    A | 0, A, B, C, ..., Z, AA, AB, ...

  Fonts
mm assumes that the font styles R (roman), I (italic), and B (bold) are mounted at font positions 1, 2, and 3, respectively. Use the fp request to mount substitute fonts at these positions as desired. The default font family is “T” (Times). To select a different one, invoke groff's fam request or use its -f command-line option.

Macros
Double-quote macro arguments that contain space characters. An explicitly empty argument may be specified with an empty pair of double quotes; for example, the following macro call has three arguments.

        .XX "foo bar" "" baz

Some macros are documented as causing a page break; this does not occur if such a macro is called when the drawing position is already at the top of a page (after a page heading, if any).

Hook macros are undefined by default; mm calls them to enable customization of its behavior. (DWB termed these “exits”.)

Macro names longer than two characters are extensions; some shorter names were not part of DWB's published interface but are documented aspects of groff mm.

1C [1]
    Format page text in one column (the default layout). The page is broken. A 1 argument suppresses this break; its use may cause body text and a pending footnote to overprint. See 2C, MC, and NCOL.

2C  Begin two-column formatting. This is a special case of MC. See 1C and NCOL.

AE  Abstract end; stop collecting abstract text. See AS.

AF [
    org-name] Specify a memorandum's organizational affiliation. At most one can be declared; org-name is used by MT memoranda and available to cover pages. See COVER.

AFX Define this hook macro to assume responsibility for formatting the affiliated firm name defined by AF in memorandum types 0 and 4 and documents using the ms cover page style. If not defined (the default), internally defined macros handle this task; see subsection “Internals” and section “Files” below. Applications include setting the firm name in a different font family or at a larger type size, drawing a rule across the page, and including a logo image using groff's PDFPIC or PSPIC macros. See MT, COVER, and groff_tmac(5).

AL [
    number-format [text-indent [ 1]]] Begin an auto-incrementing numbered list, where item numbers start at one and are followed by a dot. number-format assigns the register format (see above) mm uses for the list item enumerators. The default is 0. A text-indent argument overrides register Li. A third argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. AL calls LB; use LI to declare list items, and LE to end the list.

APP [sequence-number [title]] Begin an appendix. If sequence-number is omitted, it increments (or is initialized to 1, if necessary). The register format used for sequence-number is “A”. The page is broken. The register Aph determines whether an appendix heading is then formatted. This heading uses the string App followed by sequence-number. Appendices appear in any table of contents (see TC). The string Apptxt is set to title if the latter is present, and made empty otherwise.

APPSK sequence-number n
    [title] As APP, but increment the page number by n. Use this macro to “skip pages” when diagrams or other materials not formatted by troff are included in appendices.

AS [
    placement [indentation]] Abstract start; begin collecting abstract. Input up to the next AE call is included in the abstract. placement influences the location of the abstract on the cover page of a memorandum (see MT). COVER, by contrast, ignores placement by default, but can be customized to interpret it.

    placement | Effect
    0 | The abstract appears on page 1 and cover page if the document is a “released paper” memorandum otherwise, it appears on page 1 without a cover page.
    1 | The abstract appears only on the cover page only).

    An abstract does not appear at all in external letters (“.MT 5”). A placement of 2 was supported by DWB, but is not by groff mm.

    A second argument increases the indentation by indentation and reduces the line length by twice this amount. The default is 0.

AT title
    ... Specify author's title(s). If present, AT must appear just after the corresponding author's AU. Each title occupies an output line beneath the author's name in the signature block used by LT letters (see SG) and in MT memoranda. The ms cover page style also formats these data.

AU  [name [initials [loc [dept [ext [room [arg1 [arg2 [arg3]]]]]]]]] Specify author. AU terminates a document title started with TL, and can be called without arguments for that purpose. Author information is used by cover pages, MT memoranda, and SG. Further arguments comprise initials, location, department, telephone extension, room number or name, and up to three additional items. Repeat AU to identify multiple authors.

    Use WA/WE instead to identify the author for documents employing LT.

AV [
    name [ 1]] Format approval lines for a handwritten signature and date. Two horizontal rules are drawn, with the specified name and the text of the string Letdate, respectively, beneath them. Above these rules, mm formats the text in the string Letapp; a second argument replaces this text with one vee of vertical space. See LT.

AVL [
    name] As AV, but omitting the approval notation (the Letapp string), the date rule, and the label below the date rule (the Letdate string).

B   [bold-text [previous-font-text]] ... Join bold-text in boldface with previous-font-text in the previous font, without space between the arguments. If no arguments, switch font to bold style.

B1  Begin boxed static display. The text is indented by 1n, and the line length reduced by 2n. See DS. This is a groff mm extension.

B2  End boxed static display. See B1. This is a groff mm extension.

BE  End bottom block; see BS.

BI  [bold-text [italic-text]] ... Join bold-text in boldface with italic-text in italics, without space between the arguments.

BL [
    text-indent [ 1]] Begin bulleted list. mm marks each item with the string BU. A text-indent argument overrides register Pi. A second argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. BL calls LB; use LI to declare list items, and LE to end the list.

BR  [bold-text [roman-text]] ... Join bold-text in boldface with roman-text in roman style, without space between the arguments.

BS  Begin bottom block. mm collects input into the bottom block until the document calls BE, and outputs it between the footnote area and footer of each page.

BVL [
    text-indent [mark-indent [ 1]]] Begin broken variable-item (or “tagged”) list. Each item should supply its own mark. The line is always broken after the mark; contrast VL. A text-indent argument overrides register Pi; mark-indent sets the distance from the indentation of the current list to the mark. A third argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. BVL calls LB; use LI to declare list items, and LE to end the list.

COVER
    [style] Begin a cover page description. COVER must appear before the body text (or main matter) of a document. The argument style is used to construct the file name /usr/share/groff/1.24.1/tmac/mm/style.cov and load it with the mso request. The default style is “ms”; the ms.cov file prepares a cover page resembling that of the ms package. A .cov file must define a COVEND macro, which a document must call at the end of the cover description. Use cover description macros in the following order; only TL and AU are required.

        .COVER
        .AF
        .TL
        .AU
        .AT
        .\" Add additional AU and AT calls as needed.
        .AS
        .AE
        .COVEND

COVEND
    End the cover description.

DE  End static or floating display begun with DS or DF.

DF [
    format [fill [right-indentation]]] Begin floating display. A floating display is saved in a queue and output in the order entered. Arguments are handled as in DS. Floating displays cannot be nested. Placement of floating displays is controlled by the registers De and Df.

DL [
    text-indent [ 1]] Begin dashed list. mm marks each item with the string EM. A text-indent argument overrides register Pi. A second argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. DL calls LB; use LI to declare list items, and LE to end the list.

DS [
    format [ fill [ right-indentation]]] Begin static display. mm collects input into a display until the document calls DE. The display is output on a single page unless it is taller than the height of the page. DS can be nested (contrast with DF).

    format | Effect
    none | Do not indent the display.
    L | Do not indent the display.
    I | Indent text by
    C | Center each line.
    CB | Center the whole display as a block.
    R | Right-align each line.
    RB | Right-align the whole display as a block.

    The values “L”, “I”, “C”, and “CB” can also be specified as “0”, “1”, “2”, and “3”, respectively, for compatibility with DWB.

    fill | Effect
    none | Disable filling.
    N | Disable filling.
    F | Enable filling.

    “N” and “F” can also be specified as “0” and “1”, respectively, for compatibility with DWB.

    A third argument reduces the line length by right-indentation.

    mm normally places vertical space before and after the display. Set register Ds to “0” to suppress it.

EC  [title [override [flag [ref-name]]]] Caption an equation. A caption comprises the string Capec followed by an automatically incrementing counter stored in the register Ec, punctuation configured by the register Of, then title (if any). Use the af request to configure Ec's number format. override and flag alter the equation number as follows. Omitting flag and specifying 0 in its place are equivalent.

    flag | Effect
    0 | Prefix number with
    1 | Suffix number with
    2 | Replace number with

    mm centers equation captions irrespective of the alignment of any enclosing display.

    Specifying ref-name stores the equation number as if by “.SETR ref-name \n[Ec]”. Recognition of this argument is a groff mm extension.

    The package lists captioned equations in a table of contents (see TC) if the Boolean register Le is true. The string Le captions this list.

EF ["'
    left'center'right'" ] Define the even-page footer, which is formatted just above the normal page footer on even-numbered pages. See PF. EF defines the string EOPef.

EH ["'
    left'center'right'" ] Define the even-page header, which is formatted just below the normal page header on even-numbered pages. See PH. EH defines the string TPeh.

EN  End mathematical expression input preprocessed by eqn(1); see EQ.

EOP groff mm calls this hook macro in lieu of normal page footer layout. The package uses a separate environment to format headers and footers. See TP.

    Strings available to EOP
    EOPf | argument to PF
    EOPef | argument to EF
    EOPof | argument to OF

EPIC [
    -L] width height [name] Draw a box with the given width and height. The text name (or default text) is formatted inside the box; no attempt is made to size the box to fit the text. An application of this macro is to indicate the placement of an image to be determined later, or externally composited in postprocessing. -L as the first argument left-aligns the box; the default is to center it. See PIC.

EQ [
    label] Start mathematical expression input preprocessed by eqn(1). EQ and EN macro calls bracket an equation region. Such regions must be contained in displays (DS/DE), except when the region is used only to configure eqn and not to produce output. If present, label appears aligned to the right and centered vertically within the display; see register Eq. If multiple eqn regions occur within a display, only the last label (if any) is used.

EX  [title [override [flag [ref-name]]]] Caption an exhibit. Arguments are handled analogously to EC. The register Ex is the exhibit counter. The string Capex precedes the exhibit number and any title. mm centers exhibit captions irrespective of the alignment of any enclosing display.

    The package lists captioned exhibits in a table of contents (see TC) if the Boolean register Lx is true. The string Lx captions this list.

FC [
    closing-text] Output the string Letfc, or the specified closing-text, as the formal closing of a letter or memorandum. See LT and MT.

FD [
    arg [ 1]] Configure display of footnotes. The first argument encodes enablement of automatic hyphenation, adjustment to both margins, indentation of footnote text, and left- vs. right-alignment of the footnote label within the space allocated for it.

    arg | Hyphenate? | Adjust? | Indent? | Label alignment
    0 | no | yes | yes | left
    1 | yes | yes | yes | left
    2 | no | no | yes | left
    3 | yes | no | yes | left
    4 | no | yes | no | left
    5 | yes | yes | no | left
    6 | no | no | no | left
    7 | yes | no | no | left
    8 | no | yes | yes | right
    9 | yes | yes | yes | right
    10 | no | no | yes | right
    11 | yes | no | yes | right

    An arg greater than 11 is treated as 0. mm's default is 0.

    A second argument resets footnote numbering when a first-level heading is encountered. See FS.

FE  End footnote; see FS.

FG  [title [override [flag [ref-name]]]] Caption a figure. Arguments are handled analogously to EC. The register Fg is the figure counter. The string Capfg precedes the figure number and any title. mm centers figure captions irrespective of the alignment of any enclosing display.

    The package lists captioned figures in a table of contents (see TC) if the Boolean register Lf is true. The string Lf captions this list.

FS [
    mark] Start footnote. mm collects input into a footnote until the document calls FE, outputting it when the vertical drawing position nears the page bottom. By default, mm automatically numbers footnotes starting at 1; the number is available in register Ftnum and, with a trailing period, in string F. If desired, interpolate this string in the body text to format the footnote mark. mm interpolates string F prior to the footnote text. Footnotes are vertically separated by the product of registers Fs and Lsp. In groff mm, footnotes may be used in displays.

    A mark argument, which need not be numeric, replaces the default footnote mark, leaving the string F unchanged. In that event, you must explicitly write any footnote mark to appear in the footnote itself.

GETHN ref-name
    [string] Interpolate ref-name's heading mark, or, if string is specified, store it there. In neither case does GETHN suffix the interpolation with space. See INITR.

GETPN ref-name
    [string] Interpolate ref-name's page number, or, if string is specified, store it there. In neither case does GETPN suffix the interpolation with space. See INITR.

GETR ref-name
    Retrieve location data for reference ref-name, call GETHN and GETPN to populate strings Qrfh and Qrfn, respectively, and interpolate string Qrf as an internal reference to it. See INITR.

GETST ref-name
    [string] Interpolate ref-name's auxiliary reference datum, or, if string is specified, store it there. In neither case does GETST suffix the interpolation with space. See INITR.

H level
    [title [suffix]] Set a numbered section heading at level. mm calls LC to clear any lists, then produces numbered heading marks of the form a.b.c..., with up to fourteen levels of nesting. Each level's number increments automatically with each H call and is reset to zero when a more significant level is specified. “1” is the most significant or coarsest division of the document. Text after an H call is formatted as a paragraph; calling P is unnecessary.

    The optional title must be double-quoted if it contains spaces. mm appends suffix to title in the body of the document, but omits it from any table of contents (see TC). This facility can be used to annotate the heading title with a footnote. suffix should not interpolate the F string; specify a footnote mark explicitly. See FS.

    Heading behavior is configurable. Several registers set thresholds, where heading levels at or below a threshold value are handled in one way, and those above it another. For example, mm populates a table of contents (see TC) with the title of a heading if its level is within the Cl register threshold.

    Heading layout. Register Ej sets a threshold for page breaking (ejection) prior to a heading. If not preceded by a page break, a heading level within the threshold in register Hps is preceded by the amount of vertical space in register Hps1, and by the amount in Hps2 otherwise. The Hb register sets a threshold at which a break occurs after the heading, and register Hs sets a threshold within which vertical space follows it. If the heading level is above both of these, and the paragraph is not numbered, mm produces a run-in heading; paragraph text follows on the same output line. Otherwise, register Hi configures the indentation of text after headings. Threshold register Hc permits centering; mm centers a heading with a level within both of the Hb and Hc thresholds.

    Heading typeface and size. The HF string configures the fonts used for heading marks and titles at each level. The string HP likewise assigns a type size to each heading level. The hook macros HX and/or HZ can control the vertical spacing used by headings.

    Heading number format. Registers named H1 through H14 store counters for each heading level. Their values are printed using Arabic numerals by default; see HM. The heading levels are catenated with dots for formatting; to typeset only the deepest, set the Ht register. Heading numbers are not suffixed with a trailing dot except when only the first level is output; to omit a dot in this case as well, clear the H1dot register.

    Customizing heading behavior. H calls HX, HY, and HZ hook macros to further customize headings. These can change the heading's mark (the numbered portion before any heading title), its vertical spacing, and its vertical space requirements (for instance, to require a minimum quantity of subsequent output lines on the page, breaking the page otherwise). Define hook macros in expectation of the following parameters. The argument declared-level is the level argument to H, or 0 for unnumbered headings (see HU). actual-level is the same as declared-level for numbered headings, and the value of register Hu for unnumbered headings. title-suffix is the catenation of the corresponding arguments to H or HU.

    HX declared-level actual-level title-suffix
        mm calls HX before setting the heading. Your definition may alter }0, }2, and ;3.

        }0 (string)
            contains the heading mark plus two spaces if declared-level is non-zero, and otherwise is empty.

        ;0 (register)
            encodes a position for the text after the heading. 0 means that the heading is to be run in, 1 means that a break is to occur before the text, and 2 means that vertical space is to separate heading and text.

        }2 (string)
            is the suffix that separates a run-in heading from the text. It contains two spaces if register ;0 is 0, and otherwise is empty.

        ;3 (register)
            contains the vertical space required for the heading to be typeset. If that amount is not available, the page is broken prior to the heading. The default is 2v.

    HY declared-level actual-level title-suffix
        mm calls HY after determining the heading typeface and size. It could be used to change indentation.

    HZ declared-level actual-level title-suffix
        mm calls HZ after formatting the heading, just before H or HU returns. It could be used to change the page header to include a section heading.

HC [hyphenation-character]
    Set hyphenation character, selecting the default, “\%”, if called without argument.

HM [arg1 [arg2 [... [arg14]]]]
    Set the heading mark style. Each argument assigns the specified register format (see above) to the corresponding heading level. The default is 1 for all levels. An explicitly empty argument also indicates the default.

HU title
    [suffix] Set an unnumbered section heading with title and, as a groff mm extension, an optional suffix. The heading is treated as a numbered heading of the level stored in register Hu, but no heading mark is output; see H.

I   [italic-text [previous-font-text]] ... Join italic-text in italics with previous-font-text in the previous font, without space between the arguments. If no arguments, switch font to italic style.

IA [
    recipient-name [ title]] Specify the inside address in a letter. The arguments give each recipient a name and title. mm collects input into the inside address until the document calls IE, then outputs it. You can specify multiple recipients with empty IA/IE pairs; mm uses only the last address. See LT.

IB  [italic-text [bold-text]] ... Join italic-text in italics with bold-text in boldface, without space between the arguments.

IE  End the inside address begun with IA.

IND argument
    ... If the Boolean register Ref is true, write an index entry as a specially prepared roff comment to the standard error stream, with each argument separated from its predecessor by a tab character. The entry's location information is arranged as configured by the most recent INITI call.

INDP
    Output the index set up by INITI and populated by IND calls. By default, INDP calls SK and writes a centered caption interpolating the string Index. It then disables filling and calls 2C; afterward, it restores filling and calls 1C.

    Define macros to customize this behavior. INDP calls TXIND before the caption, TYIND instead of writing the caption, and TZIND after formatting the index.

INITI location-type file-name
    [macro] Initialize groff mm's indexing system. Argument location-type selects how the location of each index entry is reported. file-name populates an internal string used later by INDP.

    location-type | Entry format
    N | page number
    H | heading mark
    B | page number, tab character, heading mark

    If macro is specified, groff mm calls it for each index entry with the arguments given to IND.

INITR file-name-prefix
    Initialize the internal reference macros. Internal references are written to the standard error stream, which should be redirected into a file named file-name-prefix.qrf. mmroff(1) handles this and the two formatting passes it requires. The first pass identifies internal references; the second includes them. See SETR, GETHN, GETPN, and GETST.

IR  [italic-text [roman-text]] ... Join italic-text in italics with roman-text in roman style, without space between the arguments.

LB text-indent mark-indent pad type
    [mark-or-format [pre-item-space [pre-list-space]]] Begin list. The macros AL, BL, BVL, DL, ML, RL, and VL call LB in various ways; they are simpler to use and may be preferred if they suit the desired purpose.

    mm tracks the nesting level of lists; the outermost is 0. It indents each list item (text formatted after an LI call) by text-indent. The mark is left-aligned at mark-indent, and padded on the left with pad ens of space. type determines the mark's format.

    type | Output for a mark “x”
    0 | x
    1 | x.
    2 | x)
    3 | (x)
    4 | [x]
    5 | <x>
    6 | {x}

    If type is 0, mark-or-format specifies each item's mark (which can be overridden by an argument to LI). If mark-or-format is empty (or the dummy character “\&”) mm sets items at mark-indent with a hanging indent at text-indent.

    If type is greater than zero, mm supplies an automatically incrementing numeric mark, and interprets mark-or-format as a register format.

    A type of -1 causes groff mm to break the line after the mark even if it fits within text-indent; this is a groff mm extension.

    The last two arguments manage vertical space. Unless a list's nesting level is greater than the value of register Ls, its items are preceded by pre-item-space multiplied by the register Lsp; the default is 1. LB precedes the list by pre-list-space multiplied by the register Lsp; the default is 0.

LC [
    list-level] Clear list state. Active lists are terminated as if with LE, either all (the default) or only those from the current level down to list-level if specified.

LE [1]
    End list. The current list is terminated. An argument of 1 causes vertical space in the amount of register Lsp to follow the list.

LI [
    mark [pad-prefix]] Begin a list item. mm collects input into a list item until the document terminates the current list or calls LI again. By default, the item's text is preceded by any mark configured by the current list. If mark is the only argument, it replaces the mark configured in the corresponding LB call. If the width of the mark plus any pad specified in the LB call exceeds the text indentation, groff mm warns and uses one en of padding between the mark and the text. The presence of a second argument prefixes mark to the LB-configured mark and, as a groff mm extension, conditionally puts an unbreakable space between the prefix and mark per the argument's Boolean value.

LO option
    [value] Specify letter options; see LT. By default, mm recognizes the following option values. See IA regarding the inside address and string DT regarding the date.

    option | Meaning and Effect
    AT | Attention; put contents of string and left-aligned after the inside address.
    CN | Confidential; put or contents of string left-aligned after the date.
    RN | Reference; put contents of string and after the confidential notation (if any) and the date, aligned with the latter.
    SA | Salutation; put or contents of string left-aligned after the inside address and the confidential notation (if any).
    SJ | Subject; put contents of string and left-aligned after the inside address and the attention and salutation notations (if any). In letter type “SP”, is ignored and is set in full capitals.

LT [
    style] Format a letter in the designated style, defaulting to BL (see below). A letter begins with the writer's address (WA/WE), followed by the date (ND), the inside address (IA/IE), the body of the letter (P and other general-purpose mm macros), the formal closing (FC), the signature (SG), and notations (NS/NE). Any of these except the body text may be omitted. Letter options specified with LO add further annotations, which are extensible; see subsection “Internals” below.

    style | Description
    BL | Blocked: the writer's address, date, formal closing, and signature are indented to the center of the line. Everything else is left-aligned.
    SB | Semi-blocked: as but the first line of each paragraph is indented by ens.
    FB | Fully blocked: everything is left-aligned.
    SP | Simplified: as but a formal closing is omitted, and the signature is set in full capitals.

MC column-width
    [gutter-width] Begin multi-column layout. groff mm creates as many columns of column-width as the line length will permit. gutter-width is the interior spacing between columns. It defaults to column-width/15. NCOL moves to the next column, and 1C returns to single-column layout. MC is a groff mm extension, generalizing 2C. See MULB for an alternative.

ML mark
    [text-indent [ 1]] Start a marked list; the mark argument precedes each item. text-indent overrides the default indentation of the list items, which is the width of mark plus one en. A third argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. ML calls LB; use LI to declare list items, and LE to end the list.

MT  [type [addressee]] Select memorandum type. These correspond to formats used by AT&T Bell Laboratories, where the mm package was initially developed, affecting the document layout. Some of these included a cover page with a caption categorizing the document. groff mm uses type to construct the file name /usr/share/groff/1.24.1/tmac/mm/type.MT and load it with the mso request. Memorandum types 0 to 5 are supported; any other value of type is mapped to type 6. Omitting type implies 1. addressee sets a string analogous to one used by AT&T cover page macros not implemented in groff mm.

    type | Description
    0 | normal memorandum; no caption
    1 | captioned “TECHNICAL MEMORANDUM”
    2 | captioned “INTERNAL MEMORANDUM”
    3 | captioned “ADMINISTRATIVE MEMORANDUM”
    4 | released paper
    5 | external letter
    string | captioned string

    See COVER for a more flexible cover page mechanism.

MOVE y-pos [x-pos [line-length]]
    Move to a position, setting page offset to x-pos. If line-length is not given, the difference between current and new page offset is used. Use PGFORM without arguments to return to normal.

MULB
    cw1 sp1 [cw2 sp2] ... cwn Begin alternative multi-column mode. All column widths cwi must be specified, as must the amount of space spi between each column pair. MULB uses a diversion and operates in a separate environment.

MULE
    End alternative multi-column mode and emit the columns.

MULN
    Start next column in alternative column mode.

NCOL
    Start next column (only when using 2C or MC). Contrast with MULN.

ND [
    arg] Set the document's date. mm does not interpret arg; it can be a revision identifier (or empty). mm calls ND itself when initializing.

NE  End notation begun with NS; filling is enabled.

nP [
    type] As P, but set a paragraph number in the form x.yy, where x is the number of the second heading level, and yy increments with each nP call; its value is not reset when the second-level heading number changes. mm uses a register format of “00” for yy.

NS [
    code [ 1]] Declare notations, typically for letters or memoranda, of the type specified by code. The text corresponding to code is output, and filling is disabled until the document calls NE. Typically, a list of names or attachments lies within NS/NE. If code is absent or does not match one of the values listed under the Letns string description below, each line of notations is formatted as “Copy (line) to”. If a second argument, conventionally 1, is given, code becomes the entire notation and NE is not necessary. In groff mm, you can set up further notations to be recognized by NS; see the strings Letns and Letnsdef below.

OF ["'
    left'center'right'" ] Define the odd-page footer, which is formatted just above the normal page footer on odd-numbered pages. See PF. OF defines the string EOPof.

OH ["'
    left'center'right'" ] Define the odd-page header, which is formatted just below the normal page header on odd-numbered pages. See PH. OH defines the string TPoh.

OP  Ensure that subsequent text is formatted at the top of an odd-numbered page; no page break is performed if the drawing position is already there.

P [ type] Begin new paragraph. If type is missing or 0, P sets the paragraph fully left-aligned. A type of 1 indents the first line by \[Pi] ens. Set the register Pt to select a default paragraph indentation style. The register Ps determines the amount of vertical space between paragraphs.

    To set a paragraph with a hanging indent, use VL with the desired indentation as the argument, LI (with no argument), and LE.

PE  End picture input preprocessed by pic(1); see PS.

PF ["'
    left'center'right'" ] Define the page footer. The footer is formatted at the bottom of each page; the argument is otherwise as described in PH. PF defines the string EOPf. See EF, OF, and EOP.

PGFORM
    [line-length [page-length [page-offset [1]]]] Set line length, page length, and/or page offset. This macro can be used for letterheads and similar. It is normally the first macro call in a file, though it is not necessary. PGFORM can be used without arguments to reset everything after a MOVE call. A line break is done unless the fourth argument is given. This can be used to avoid the page number on the first page while setting new width and length. (It seems as if this macro sometimes doesn't work too well. Use the command-line arguments to change line length, page length, and page offset instead.)

PGNH
    Suppress header on the next page. To suppress a header on the first page, call this macro prior to formatting any text in the document. Also see register N.

PH ["'
    left'center'right'" ]
    Define the page header, formatted at the top of each page, as the argument, where left, center, and right are aligned to the respective locations on the line. A “%” character in arg is replaced by the page number. If the argument is absent, no page header is set. The default page header is
            "''- % -''"
    which centers the page number between hyphens and formats nothing at the upper left and right. Header macros call PX (if defined) after formatting the header. PH defines the string TPh. See EH, OH, and TP.

PIC [-B] [-C| -I n |-L |-R] file [width [height]] Include PostScript document file. The optional -B argument draws a box around the picture. The optional -L, -C, -R, and -I n arguments align the picture or indent it by n. By default, the picture is left-aligned. Optional width and height arguments resize the picture. Use of this macro requires two-pass processing; see INITR and mmroff(1).

PS  Start picture input preprocessed by pic(1).

PY  As PE, but with “flyback”, returning the drawing position to where it was prior to the picture. This is a groff mm extension.

R   [roman-text [previous-font-text]] ... Join roman-text in roman style with previous-font-text in the previous font, without space between the arguments. If no arguments, switch font to roman style.

RB  [roman-text [bold-text]] ... Join roman-text in roman style with bold-text in boldface, without space between the arguments.

RD  [prompt [div [str]]] Write prompt (if specified, a tab and colon “:” to the standard error stream and read response from standard input stream, optionally into a diversion div and/or string str. Interpolate the saved text by calling its name like a macro. If string is present, the input is also stored in a string of that name.

RF  End a bibliographic reference citiation started with RS. See RP.

RI  [roman-text [italic-text]] ... Join roman-text in roman style with italic-text in italics, without space between the arguments.

RL [
    text-indent [ 1]] Begin an auto-incrementing numbered list, where item numbers start at one and set between square brackets. A text-indent argument overrides register Li. A second argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. RL calls LB; use LI to declare list items, and LE to end the list. “RL” is a mnemonic for “reference list”, but this macro has no relationship with mm's bibliographic reference list facilities.

RP  [suppress-counter-reset [page-ejection-policy]] Format a reference list, listing items accumulated within RS/RF pairs. The reference counter is reset unless the first argument is 1. Normally, page breaks occur before and after the references are output; the register Rpej configures this behavior, and a second argument overrides its value. TC calls RP automatically if references have accumulated.

    groff mm calls LB to format the reference list; the Rpfmt string configures the list's appearance. Setting register Ls to 0 suppresses spacing after the list. The string Rp contains the reference list caption.

RPX This hook macro assumes responsibility for formatting the heading of the reference page that RP produces. If not defined (the default), mm sets the reference list caption in the string Rp after two vees of space, centered in italics, followed by another vee of space.

RS [
    reference-string] Begin citation of an automatically numbered bibliographic reference entry. mm collects input into a reference entry until the document calls RF. A subsequent RP call emits the accumulated entries. References are numbered starting at 1; the register :R stores the most recently assigned number. Interpolate the string Rf where the reference mark should be, then place the entry between RS and RF calls on text lines after the reference mark. The Rfstyle register determines whether the mark is bracketed, superscripted, or both. If reference-string is specified, mm also stores the reference mark in a string of that name.

S [ type-size [vertical-spacing]] Set type size and vertical spacing. Each argument is a groff measurement, using an appropriate scaling unit and an optional + or - prefix to increment or decrement the current value. An argument of P restores the previous value, C retains the current value, and D requests the default. mm treats an empty or omitted argument as P.

SA  [mode] Set or restore the default enablement of adjustment. Specify 0 or 1 as mode to set a document's default explicitly; groff mm assumes 1. Invoke the na request as desired to temporarily suspend adjustment. H and HU, and SA when called without a mode argument, restore the default adjustment.

SETR ref-name
    [string] Create reference ref-name, storing its heading and page numbers. If string is present, groff mm saves it as an auxiliary datum for retrieval by GETST. See INITR.

SG [
    arg [ 1]] Output author signature block(s) in LT letters and MT memoranda. The format of a signature block depends on the letter or memorandum type. See subsection “Internals” below.

    LT letters emit a signature for one author at most (see WA). The author's title, if any, is set on the next line, indented to align with the name, except in letter type “SP”, where it is set in full capitals (like the name) after a comma and space.

    Memorandum type 4 uses no signature block. In other memoranda, each of an author's titles is set on a subsequent line, indented to align with the name. They furthermore encode a secretarial annotation including the location, department, and initials specified in each author's AU call, followed by any arg, writing it at the left margin preceding the last author's name, or preceding the first if a second SG argument is present.

SK  [n] Skip n pages. If n is 0 or omitted, mm breaks the page if necessary. Otherwise, mm prints n pages, blank except for any headers and footers.

SM text
    [post]
SM pre text post
    Format text at a smaller type size, joined with any specified pre and post at normal size, without space between the arguments.

SP  [distance] Space downward by distance. Multiple SP calls in sequence produce only the largest of the specified distances. SP accepts boundary-relative motions specified with a prefixed | operator, but not negative ones.

    SP has no effect when the drawing position is at the top of the page. Put the dummy character escape sequence \& (followed by \c if desired to prevent a break) on a text line prior to an SP call to overcome this restriction.

TAB Reset tab stops to every 5 ens. The ta request customizes them.

TB  [title [override [flag [ref-name]]]] Caption a table. Arguments are handled analogously to EC. The register Tb is the table counter. The string Captb precedes the table number and any title. mm centers table captions irrespective of the alignment of any enclosing display.

    The package lists captioned tables in a table of contents (see TC) if the Boolean register Lt is true. The string Lt captions this list.

TC  [slevel [spacing [tlevel [tab [h1 [h2 [h3 [h4 [h5]]]]]]]]] Output table of contents. This macro is normally the last called in the document. It flushes any pending displays and, if any references are pending (see RS), calls RP. It then begins a new page with the contents caption, stored in the string Captc, centered at the top. The entries follow after three vees of space. Each entry is a saved section (number and) heading title (see the Cl register), along with its associated page number. By default, mm indents an entry by an amount corresponding to its heading level and the maximum heading length encountered at that heading level; if defined, the string Ci overrides these indentations. Entries at heading levels up to and including slevel are preceded by spacing vees of space. Entries at heading levels up to and including tlevel are followed by a leader and a right-aligned page number. If the Boolean-valued tab argument is true, the leader is replaced with horizontal motion in the same amount. For entries above heading level tlevel, the page number follows the heading text after a word space. Each argument h1...h5 appears in order on its own line, centered, above the contents caption. Page numbering restarts at 1, in register format “i”. If the Oc register is true, numbering of these pages is suppressed.

    If the document calls TC with at most four arguments, mm calls the hook macro TX prior to formatting the contents caption, and TY (if defined) instead of formatting the contents caption.

    mm then presents lists of figures, tables, equations, and exhibits, in that order. A list appears only if at least one such captioned item is present, and if its corresponding register (Le, Lf, Lt, or Lx) is set. TXxx and TYxx macros, where xx is “FG”, “TB”, “EC”, or “EX”, and strings Capfg, Captb, Capec, and Capex analogously configure the output of each captioned list.

TE  End tbl(1) table. See TS.

TH  Mark the end of a TS/TE table heading. When a table spans multiple pages, the heading repeats at the top of each page. groff mm does not implement the N argument supported by DWB.

TL [
    charging-case-number [ filing-case-number]] Begin document title. mm collects input into the title until a subsequent AU call and formats it as directed by the MT memorandum type or cover page macros. mm saves charging-case-number and filing-case-number for use in all memorandum types except 4.

TM number
    ... Declare technical memorandum number(s) used with MT memoranda.

TP  mm calls this hook macro in lieu of normal page header layout. The package uses a separate environment to format headers and footers. See EOP.

    Strings available to TP
    TPh | argument to PH
    TPeh | argument to EH
    TPoh | argument to OH

TS [H]
    Start tbl(1) table. Argument “H” tells mm that the table's heading should repeat after page breaks. See TE, TH, and tbl(1).

VERBON
    [format [type-size [font]]] Begin display of verbatim content. format controls several parameters. Add up the values of desired features; the default is 0. Further arguments configure the type-size in typographical points (on typesetting devices), and the face (font). On typesetting devices, the default face is CR (Courier roman), a monospaced font: all glyphs are equally wide.

    Value | Effect
    1 | Disable the formatter's escape character (\).
    2 | Vertically space before the display.
    4 | Vertically space after the display.
    8 | Number output lines; call formatter's request with arguments in string
    16 | Indent by the amount stored in register

VERBOFF
    End verbatim display.

VL [
    text-indent [mark-indent [ 1]]] Begin variable-item (or “tagged”) list. Each item should supply its own mark, or tag. A text-indent argument overrides register Pi; mark-indent sets the distance from the indentation of the current list to the mark. A third argument suppresses the vertical space that normally precedes each list item; see register Lsp. Vertical space in the amount of Lsp precedes the list itself, but does not accumulate with pre-item space when this list is nested in another. RL calls LB; use LI to declare list items, and LE to end the list.

VM [-T] [top [bottom]]
    Configure vertical margins.

    Without a -T argument, increment the top and bottom margins by top and bottom, respectively. If absent, set the corresponding margin to zero.

    With the -T argument, set the top and bottom margins to top and bottom, respectively. If absent, set the respective margin to the default (top: 7v, bottom: 6v).

    We recommend defining the hook macros TP and/or EOP if using -T and setting top and/or bottom margin to values less than the default. groff mm exposes this undocumented DWB macro to enable greater user control of page layout.

WA [
    writer's-name [ title]] Specify the writer(s) of an LT letter. mm collects input into the writer's address until the document calls WE, then outputs it. You can specify multiple writers with empty WA/WE pairs; only the last address is used. The arguments give each writer a name and title.

WC [
    format ...] Control width of footnotes and displays.

    format | Effect
    N | equivalent to (default)
    WF | set footnotes at full line length, even in two-column mode
    -WF | set footnotes using column line length
    FF | apply width of first footnote to encountered to subsequent ones
    -FF | footnote width determined by and
    WD | set displays at full line length, even in two-column mode
    -WD | set displays using column line length

WE  End the writer's address begun with WA.

Strings
Many mm strings interpolate predefined, localizable text. We present their contents in quotation marks.

Abstract
    “ABSTRACT”

App “APPENDIX”

Apptxt
    stores the title argument to the most recent APP call.

Aumt
    lists space-separated indices of positional arguments to the AU macro that should be suppressed from appearance in the document heading on the first page of MT memorandum types 0–3 and 6. By default, it is undefined; all arguments are formatted except the second (author initials).

BU  interpolates a bullet mark, \[bu].

Capec
    “Equation”

Capex
    “Exhibit”

Capfg
    “Figure”

Captb
    “Table”

Captc
    “CONTENTS”

Ci  assigns indentation amounts used by each heading level listed in a table of contents, in one-to-one correspondence, overriding those computed by TC. Each word must be a horizontal measurement (like “1i”).

DT  stores the date or other identifier set by ND, if called, and otherwise one constructed using the formatter's date registers; see groff(1). The groff locale determines its format, but register Isodate may override it.

EM  interpolates an em dash, \[em].

F   interpolates an automatically numbered footnote mark; the number is used by the next FS call without an argument. In troff mode, the mark is superscripted; in nroff mode, it is surrounded by square brackets.

H1txt
    stores the text of the current first-level heading; H and HU update it, as does TC when processing table of contents entries and captions of displayed figures, tables, equations, and exhibits.

HF  assigns font identifiers, separated by spaces, to heading levels in one-to-one correspondence. Each identifier may be a font mounting position, font name, or style name. Omitted values are assumed to be 1. The default is “2 2 2 2 2 2 2 2 2 2 2 2 2 2”, which places all headings in italics. DWB's default was “3 3 2 2 2 2 2”.

HP  assigns type sizes, separated by spaces, to heading levels in one-to-one correspondence. groff mm interprets each size in typographical points, translating zero values to 10. Omitted values are assumed to be 0 (and are translated accordingly). The default is “0 0 0 0 0 0 0 0 0 0 0 0 0 0”.

Index
    “INDEX”

Le  “LIST OF EQUATIONS”

Letfc
    “Yours very truly,” (see FC)

Letapp
    “APPROVED:” (see AV)

LetAT
    “ATTENTION:” (see LO)

LetCN
    “CONFIDENTIAL” (see LO)

Letdate
    “Date” (see AV)

Letns
    is a group of strings structuring the notations produced by NS. If the code argument to NS has no corresponding string, the notation is included between parentheses, prefixed with Letns!copy, and suffixed with Letns!to. Observe the spaces after “Copy” and before “to”.

    NS code | String | Contents
    0 | Letns!0 | Copy to
    1 | Letns!1 | Copy (with att.) to
    2 | Letns!2 | Copy (without att.) to
    3 | Letns!3 | Att.
    4 | Letns!4 | Atts.
    5 | Letns!5 | Enc.
    6 | Letns!6 | Encs.
    7 | Letns!7 | Under separate cover
    8 | Letns!8 | Letter to
    9 | Letns!9 | Memorandum to
    10 | Letns!10 | Copy (with atts.) to
    11 | Letns!11 | Copy (without atts.) to
    12 | Letns!12 | Abstract Only to
    13 | Letns!13 | Complete Memorandum to
    14 | Letns!14 | CC
    — | Letns!copy | Copy (with trailing space)
    — | Letns!to | to (note leading space)

Letnsdef
    selects the notation format when NS is given no argument. The default is 0.

LetRN
    “In reference to:” (see LO)

LetSA
    “To Whom It May Concern:” (see LO)

LetSJ
    “SUBJECT:” (see LO)

Lf  “LIST OF FIGURES”

Lt  “LIST OF TABLES”

Lx  “LIST OF EXHIBITS”

MO1
...
MO12
    “January” through “December”

Qrf “See chapter \E*[Qrfh], page \En[Qrfp].” If your document uses multiple heading levels, you might redefine this string to use the word “section” instead of “chapter”.

Qrfh
    stores the heading mark corresponding to the most recent GETR call.

Qrfp
    stores the page number corresponding to the most recent GETR call.

Rf  interpolates an automatically numbered reference mark; the number is used by the next RS call.

Rp  “REFERENCES”

Rpfmt
    specifies the LB arguments that groff mm uses to format the items in an RP reference list. The default is “\\n[Li] 0 1 0 \& 0”.

Rg  interpolates the registered (trade) mark sign.

Sm  interpolates the service mark sign.

Tcstatus
    interpolates an indicator of the TC macro's processing status. If TC is not operating, it is empty. User-defined TP or EOP macros might condition page headers or footers on its contents.

    Value | Meaning
    co | Table of contents
    fg | List of figures
    tb | List of tables
    ec | List of equations
    ex | List of exhibits
    ap | Appendix

Tm  interpolates ™, the trade mark sign.

Verbnm
    supplies argument(s) to the nm request employed by the VERBON macro. The default is 1.

Registers
Default register values, where meaningful, are shown in parentheses.

.mgm
    indicates that groff mm is in use (Boolean-valued; 1).

Aph formats an appendix heading (and title, if supplied); see APP (Boolean-valued; 1).

Au  includes supplemental author information (the third and subsequent arguments to AU) in memorandum “from” information; see COVER and MT, and the Aumt string (Boolean-valued; 1).

Cl  sets the threshold for inclusion of headings in a table of contents. Headings at levels above this value are excluded; see H and TC. The Cl register controls whether a heading is saved for output in the table of contents at the time H or HU is called; if you change Cl's value immediately prior to calling TC, you are unlikely to get the result you want (2).

Cp  suppresses page breaks before lists of captioned equations, exhibits, figures, and tables, and before an index; see EC, EX, FG, TB, and INDP (Boolean-valued; 0).

D   produces debugging information for the mm package on the standard error stream. A value of 0 outputs nothing; 1 reports formatting progress. Higher values communicate internal state information of increasing verbosity (0).

De  causes a page break after a floating display is output; see DF (Boolean-valued; 0).

Df  configures the behavior of DF. The following values are recognized; 4 and 5 do not override the De register (5).

    Value | Effect
    0 | Flush pending displays at the end of each section when section-page numbering is active, otherwise at the end of the document.
    1 | Flush a pending display on the current page or column if there is enough space, otherwise at the end of the document.
    2 | Flush one pending display at the top of each page or column.
    3 | Flush a pending display on the current page or column if there is enough space, otherwise at the top of the next.
    4 | Flush as many pending displays as possible in a new page or column.
    5 | Fill columns or pages with flushed displays until none remain.

Ds  puts vertical space in the amount of register Dsp (if defined) or Lsp before and after each static display; see DS (Boolean-valued; 1).

Dsp configures the amount of vertical space placed before and after static displays; see DS and register Ds (undefined).

Ec  is an auto-incrementing equation counter; see EC.

E   determines the font style used by MT memoranda, LT letters, and the ms.cov cover page style to set the date and certain other document data; 0 selects roman, and 1 bold (Boolean-valued; 1).

Ej  sets the threshold for page breaks (ejection) prior to the format of headings. Headings at levels above this value are set on the same page and column as any preceding text if possible; see H (0).

Eq  aligns an equation label to the left of a display instead of the right (Boolean-valued; 0).

Ex  is an auto-incrementing exhibit counter; see EX.

Fg  is an auto-incrementing figure counter; see FG.

Fs  is multiplied by register Lsp to vertically separate footnotes; see FS (1).

Ftnum
    is an auto-incrementing footnote counter; see FS. groff mm recognizes :p as an alias of Ftnum for DWB compatibility.

H1
...
H14
    are auto-incrementing counters corresponding to each heading level; see H.

H1dot
    appends a period to the number of a level one heading; see H (Boolean-valued; 1).

H1h is a copy of register H1, but it is incremented just before a page break. This can be useful in hook macros; see H and HX.

Hb  sets the threshold for breaking the line after formatting a heading. Text after headings at levels above this value is set on the same output line if possible. Paragraphs numbered via nP or the Np register cause a break regardless; see H (2).

Hc  sets the threshold for centering a heading. Headings at levels above this value use the prevailing alignment (that is, they are not centered); see H (0).

Hi  selects an indentation policy for text formatted after headings. It does not affect “run-in” headings. The following values are recognized; see H and P (1).

    Value | Effect
    0 | no indentation
    1 | indent per the paragraph type
    2 | indent to align with heading title

Hps sets the heading level threshold for application of preceding vertical space; see H. Headings at levels above the value in register Hps use the amount of space in register Hps1; otherwise that in Hps2. The value of Hps should be strictly greater than that of Ej (1).

Hps1
    configures the amount of vertical space preceding a heading above the Hps threshold; see H (troff devices: 0.5v; nroff devices: 1v).

Hps2
    configures the amount of vertical space preceding a heading within the Hps threshold; see H (troff devices: 1v; nroff devices: 2v).

Hs  sets the heading level threshold for application of succeeding vertical space. If the heading level is greater than Hs, the heading is followed by vertical space in the amount of register Hss; see H (2).

Hss is multiplied by register Lsp to produce vertical space after headings above the threshold in register Hs; see H (1).

Ht  suppresses output of heading level counters above the deepest when a heading mark is formatted; see H (Boolean-valued; 0).

Hu  sets the heading level used by unnumbered headings; see HU (2).

Hy  enables automatic hyphenation of words (Boolean-valued; 0).

Isodate
    configures the use of ISO 8601 date format; that is, YYYY-MM-DD instead of the format specified by the localization file. Call ND without arguments after updating its value (Boolean-valued; 0).

L   defines the page length for the document, and must be set from the command line. A scaling unit should be appended. The default is that of the selected groff output device.

Le
Lf
Lt
Lx
    configure the report of lists of equation, figure, table, and exhibit captions, respectively, after a table of contents; see TC (all: Boolean-valued; 1).

Letwam
    sets the maximum number of input lines permitted in a writer's address; see WA and WE (14).

Li  configures the text indentation (in ens) applied to enumerated list types; that is, to items in AL and RL lists, and in LB lists whose type argument is greater than zero (5).

Ls  sets a threshold for placement of vertical space before list items. If the list nesting level is greater than this value, no such spacing occurs; see LI (\n[.R]).

Lsp configures the base amount of vertical space used for separation in the document. mm applies this spacing to many contexts, sometimes with multipliers; see DS, FS, H, LI, and P (troff devices: 0.5v; nroff devices: 1v).

N   configures the header and footer placements used by PH. The default footer is empty. If “section-page” numbering is selected, the default header becomes empty and the default footer becomes “x-y”, where x is is the section number (the number of the current first-level heading) and y the page number within the section. The following values are recognized; for finer control, see PH, PF, EH, EF, OH, and OF, and registers Sectf and Sectp. Value 5 is a groff mm extension (0).

    Value | Effect
    0 | Set header on all pages.
    1 | Move header to footer on page 1.
    2 | Omit header on page 1.
    3 | Use “section-page” numbering style on all pages.
    4 | Omit header on all pages.
    5 | Use “section-page” and “section-figure” numbering style on all pages.

Np  numbers paragraphs with a leading mark in the format s.p, where s is is first-level heading number and p is the paragraph number, starting at 1; see H and P (Boolean-valued; 0).

O   defines the page offset of the document, and must be set from the command line. A scaling unit should be appended. The default is .75i on terminal devices. On typesetters, it is .963i or set to 1i by the papersize.tmac package; see groff_tmac(5).

Oc  suppresses the appearance of page numbers in the table of contents; see TC (Boolean-valued; 0).

Of  selects a separator format within equation, exhibit, figure, and table captions; see EC, EX, FG, and TB. The punctuation in the separator is either a dot or the EM string. The following values are recognized; the spaces shown are unpaddable (0).

    Value | Effect
    0 | ". "
    1 | " — "

P   interpolates the current page number; it is the same as register % except when “section-page” numbering is enabled.

Pi  configures the indentation (in ens) applied to the first line of an unnumbered paragraph that has such (see P); and the text indentation of non-enumerated list items; that is, to items in BL, BVL, DL, and VL lists (but not ML), and in LB lists whose type argument is zero or less (5).

Pgps
    causes the type size and vertical spacing set by S to apply to headers and footers, overriding the HP string. If not set, S calls affect headers and footers only when followed by PH, PF, OH, EH, OF, or EF calls (Boolean-valued; 1).

Ps  is multiplied by register Lsp to vertically separate paragraphs; see P (1).

Pt  determines when a first-line indentation is applied to a paragraph; see P (0).

    Value | Effect
    0 | never
    1 | always
    2 | always, except immediately after or

Ref is used internally to control mmroff(1)'s two-pass approach to index and reference management; see IND, INDP, INITI, INITR, and PIC (Boolean-valued; 0).

Rfnum
    is an auto-incrementing reference counter; see RS. groff mm recognizes :R as an alias of Rfnum for DWB compatibility.

Rfstyle
    determines the format of the reference number in the Rf string. groff mm maps 0 to 1 in nroff mode and 2 in troff mode (0).

    Value | Meaning
    0 | automatic
    1 | bracketed
    2 | superscripted
    3 | bracketed and superscripted

    Changes to Rfstyle's value may not take effect until the next heading or paragraphing macro call.

Rpej
    configures the default page ejection policy for reference pages; see RP (0).

    Value | Effect
    0 | Break the page before and after the reference list.
    1 | Suppress page break after the list.
    2 | Suppress page break before the list.
    3 | Suppress page breaks before and after the list.

S   defines the type size for the document, and must be set from the command line. A scaling unit should be appended; p is typical (10p).

Sectf
    selects the “section-figure” numbering style. Its default is 0 unless register N is set to 5 at the command line (Boolean-valued).

Sectp
    selects the “section-page” numbering style. Its default is 0 unless register N is set to 3 or 5 at the command line (Boolean-valued).

Si  configures the amount of display indentation in ens; see DS (5).

Tb  is an auto-incrementing table counter; see TB.

V   defines the vertical spacing for the document, and must be set from the command line. A scaling unit should be appended; p is typical. The default vertical spacing is 120% of the type size. This register is a groff mm extension.

Verbin
    configures the amount of indentation for verbatim displays when indentation is selected; see VERBON (5n).

W   defines the “width” of the document (that is, the length of an output line with no indentation); it must be set from the command line. A scaling unit should be appended. The default is 6i or assigned by the papersize.tmac package; see groff_tmac(5).

  Internals
The argument (if any) to a COVER or MT call determines the file that groff mm loads to configure the document's layout; see section “Files” below.

LT's behavior depends on the style argument given to it; it calls macros with names suffixed accordingly. It is therefore possible to define additional letter types, either in the territory-specific macro file, or as local additions. LT sets the registers Pt and Pi to 0 and 5, respectively. (DWB used a value of 3 for Pi.) It then calls an initialization macro corresponding to the type. Define the following macros to support a new letter type.

let@init_type
    initializes any registers and other data needed by the letter type.

let@head_type
    formats the letterhead; it is called instead of the usual page header macro. Its definition should remove the alias let@header unless the letterhead is desired on subsequent pages.

let@sg_type
    name title n is-final [SG-arg ...] is called by SG only for LT letters; MT memoranda implement their own signature processing. name and title are specified through WA/WE. n is the index of the nth writer, and is-final is true for the last writer to be listed. Further SG arguments are appended to the signature line.

let@fc_type closing
    is called by FC, and takes the formal closing as its argument.

LO implements letter options. It requires that a string named Lettype be defined, where type is the letter type. LO then assigns its second argument (value) to the string let*lo-type .

Files

/usr/share/groff/1.24.1/tmac/m.tmac
    is the groff implementation of the memorandum macros.

/usr/share/groff/1.24.1/tmac/mm.tmac
    is a wrapper enabling the package to be loaded with the option “-m mm”.

/usr/share/groff/1.24.1/tmac/refer-mm.tmac
    implements refer(1) support for mm.

/usr/share/groff/1.24.1/tmac/mm/ms.cov
    implements an ms-like cover page.

/usr/share/groff/1.24.1/tmac/mm/0.MT
    implements memorandum types 0–3 and 6.

/usr/share/groff/1.24.1/tmac/mm/4.MT
    implements memorandum type 4.

/usr/share/groff/1.24.1/tmac/mm/5.MT
    implements memorandum type 5.

/usr/share/groff/1.24.1/tmac/mm/locale
    performs any (further) desired localization if present.

/usr/share/doc/groff-base/examples/letter.mm
    illustrates features of the LT letter formats.

/usr/share/doc/groff-base/examples/memorandum.mm
    illustrates features of the MT memorandum formats.

/usr/share/doc/groff-base/examples/story.mm
    illustrates use of mm for literary purposes.

Authors
Jörgen Hägg (jh@axis.se) of Lund, Sweden, wrote the version of the mm macro package distributed with groff based on an early version of groff ms by James Clark (jjc@jclark.com). Werner Lemberg (wl@gnu.org) and G. Branden Robinson (g.branden.robinson@gmail.com) revised and updated it.

See also
MM - A Macro Package for Generating Documents (https://tkurtbond.github.io/troff/mm-all.pdf), the DWB 3.3 mm manual, introduces the package but does not document groff mm extensions.

Groff: The GNU Implementation of troff, by Trent A. Fisher and Werner Lemberg, is the primary groff manual. You can browse it interactively with “info groff”.

groff(1), troff(1), tbl(1), pic(1), eqn(1), refer(1), groff_mmse(7) (only in Swedish locales)