[BACK]Return to roff.7 CVS log [TXT][DIR] Up to [cvsweb.bsd.lv] / mandoc

Annotation of mandoc/roff.7, Revision 1.76

1.76    ! schwarze    1: .\"    $Id: roff.7,v 1.75 2015/09/24 18:41:22 schwarze Exp $
1.1       kristaps    2: .\"
1.46      schwarze    3: .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
1.74      schwarze    4: .\" Copyright (c) 2010, 2011, 2013-2015 Ingo Schwarze <schwarze@openbsd.org>
1.1       kristaps    5: .\"
                      6: .\" Permission to use, copy, modify, and distribute this software for any
                      7: .\" purpose with or without fee is hereby granted, provided that the above
                      8: .\" copyright notice and this permission notice appear in all copies.
                      9: .\"
                     10: .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
                     11: .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
                     12: .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
                     13: .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
                     14: .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
                     15: .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
                     16: .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
                     17: .\"
1.76    ! schwarze   18: .Dd $Mdocdate: September 24 2015 $
1.1       kristaps   19: .Dt ROFF 7
                     20: .Os
                     21: .Sh NAME
                     22: .Nm roff
1.17      schwarze   23: .Nd roff language reference for mandoc
1.1       kristaps   24: .Sh DESCRIPTION
                     25: The
                     26: .Nm roff
1.17      schwarze   27: language is a general purpose text formatting language.
1.33      schwarze   28: Since traditional implementations of the
1.17      schwarze   29: .Xr mdoc 7
                     30: and
                     31: .Xr man 7
1.33      schwarze   32: manual formatting languages are based on it,
                     33: many real-world manuals use small numbers of
1.17      schwarze   34: .Nm
1.46      schwarze   35: requests and escape sequences intermixed with their
1.33      schwarze   36: .Xr mdoc 7
                     37: or
                     38: .Xr man 7
                     39: code.
                     40: To properly format such manuals, the
1.1       kristaps   41: .Xr mandoc 1
1.33      schwarze   42: utility supports a tiny subset of
                     43: .Nm
1.46      schwarze   44: requests and escapes.
                     45: Only these requests and escapes supported by
1.33      schwarze   46: .Xr mandoc 1
                     47: are documented in the present manual,
                     48: together with the basic language syntax shared by
                     49: .Nm ,
                     50: .Xr mdoc 7 ,
                     51: and
                     52: .Xr man 7 .
                     53: For complete
                     54: .Nm
                     55: manuals, consult the
                     56: .Sx SEE ALSO
                     57: section.
1.1       kristaps   58: .Pp
1.33      schwarze   59: Input lines beginning with the control character
1.17      schwarze   60: .Sq \&.
1.33      schwarze   61: are parsed for requests and macros.
                     62: Such lines are called
                     63: .Dq request lines
1.1       kristaps   64: or
1.33      schwarze   65: .Dq macro lines ,
                     66: respectively.
                     67: Requests change the processing state and manipulate the formatting;
                     68: some macros also define the document structure and produce formatted
                     69: output.
                     70: The single quote
                     71: .Pq Qq \(aq
                     72: is accepted as an alternative control character,
                     73: treated by
                     74: .Xr mandoc 1
                     75: just like
                     76: .Ql \&.
                     77: .Pp
                     78: Lines not beginning with control characters are called
                     79: .Dq text lines .
                     80: They provide free-form text to be printed; the formatting of the text
                     81: depends on the respective processing context.
1.1       kristaps   82: .Sh LANGUAGE SYNTAX
                     83: .Nm
                     84: documents may contain only graphable 7-bit ASCII characters, the space
1.17      schwarze   85: character, and, in certain circumstances, the tab character.
1.38      kristaps   86: The backslash character
1.33      schwarze   87: .Sq \e
1.46      schwarze   88: indicates the start of an escape sequence, used for example for
1.33      schwarze   89: .Sx Comments ,
                     90: .Sx Special Characters ,
                     91: .Sx Predefined Strings ,
                     92: and
                     93: user-defined strings defined using the
                     94: .Sx ds
                     95: request.
1.46      schwarze   96: For a listing of escape sequences, consult the
                     97: .Sx ESCAPE SEQUENCE REFERENCE
                     98: below.
1.33      schwarze   99: .Ss Comments
                    100: Text following an escaped double-quote
                    101: .Sq \e\(dq ,
                    102: whether in a request, macro, or text line, is ignored to the end of the line.
                    103: A request line beginning with a control character and comment escape
                    104: .Sq \&.\e\(dq
                    105: is also ignored.
                    106: Furthermore, request lines with only a control character and optional
                    107: trailing whitespace are stripped from input.
                    108: .Pp
                    109: Examples:
                    110: .Bd -literal -offset indent -compact
                    111: \&.\e\(dq This is a comment line.
                    112: \&.\e\(dq The next line is ignored:
                    113: \&.
                    114: \&.Sh EXAMPLES \e\(dq This is a comment, too.
                    115: \&example text \e\(dq And so is this.
                    116: .Ed
                    117: .Ss Special Characters
                    118: Special characters are used to encode special glyphs and are rendered
                    119: differently across output media.
                    120: They may occur in request, macro, and text lines.
                    121: Sequences begin with the escape character
                    122: .Sq \e
                    123: followed by either an open-parenthesis
                    124: .Sq \&(
                    125: for two-character sequences; an open-bracket
                    126: .Sq \&[
                    127: for n-character sequences (terminated at a close-bracket
                    128: .Sq \&] ) ;
                    129: or a single one character sequence.
                    130: .Pp
                    131: Examples:
                    132: .Bl -tag -width Ds -offset indent -compact
                    133: .It Li \e(em
                    134: Two-letter em dash escape.
                    135: .It Li \ee
                    136: One-letter backslash escape.
                    137: .El
                    138: .Pp
                    139: See
1.17      schwarze  140: .Xr mandoc_char 7
1.33      schwarze  141: for a complete list.
                    142: .Ss Text Decoration
                    143: Terms may be text-decorated using the
                    144: .Sq \ef
                    145: escape followed by an indicator: B (bold), I (italic), R (regular), or P
                    146: (revert to previous mode).
                    147: A numerical representation 3, 2, or 1 (bold, italic, and regular,
                    148: respectively) may be used instead.
1.34      kristaps  149: The indicator or numerical representative may be preceded by C
                    150: (constant-width), which is ignored.
1.33      schwarze  151: .Pp
1.42      schwarze  152: The two-character indicator
                    153: .Sq BI
                    154: requests a font that is both bold and italic.
                    155: It may not be portable to old roff implementations.
                    156: .Pp
1.33      schwarze  157: Examples:
                    158: .Bl -tag -width Ds -offset indent -compact
                    159: .It Li \efBbold\efR
1.42      schwarze  160: Write in \fBbold\fP, then switch to regular font mode.
1.33      schwarze  161: .It Li \efIitalic\efP
1.42      schwarze  162: Write in \fIitalic\fP, then return to previous font mode.
                    163: .It Li \ef(BIbold italic\efP
                    164: Write in \f(BIbold italic\fP, then return to previous font mode.
1.33      schwarze  165: .El
                    166: .Pp
                    167: Text decoration is
                    168: .Em not
                    169: recommended for
                    170: .Xr mdoc 7 ,
                    171: which encourages semantic annotation.
                    172: .Ss Predefined Strings
                    173: Predefined strings, like
                    174: .Sx Special Characters ,
                    175: mark special output glyphs.
                    176: Predefined strings are escaped with the slash-asterisk,
                    177: .Sq \e* :
                    178: single-character
                    179: .Sq \e*X ,
                    180: two-character
                    181: .Sq \e*(XX ,
                    182: and N-character
                    183: .Sq \e*[N] .
                    184: .Pp
                    185: Examples:
                    186: .Bl -tag -width Ds -offset indent -compact
                    187: .It Li \e*(Am
                    188: Two-letter ampersand predefined string.
                    189: .It Li \e*q
                    190: One-letter double-quote predefined string.
                    191: .El
                    192: .Pp
                    193: Predefined strings are not recommended for use,
                    194: as they differ across implementations.
                    195: Those supported by
                    196: .Xr mandoc 1
                    197: are listed in
                    198: .Xr mandoc_char 7 .
                    199: Manuals using these predefined strings are almost certainly not portable.
                    200: .Ss Whitespace
                    201: Whitespace consists of the space character.
                    202: In text lines, whitespace is preserved within a line.
                    203: In request and macro lines, whitespace delimits arguments and is discarded.
                    204: .Pp
                    205: Unescaped trailing spaces are stripped from text line input unless in a
                    206: literal context.
                    207: In general, trailing whitespace on any input line is discouraged for
                    208: reasons of portability.
                    209: In the rare case that a blank character is needed at the end of an
                    210: input line, it may be forced by
                    211: .Sq \e\ \e& .
                    212: .Pp
                    213: Literal space characters can be produced in the output
                    214: using escape sequences.
                    215: In macro lines, they can also be included in arguments using quotation; see
                    216: .Sx MACRO SYNTAX
                    217: for details.
                    218: .Pp
                    219: Blank text lines, which may include whitespace, are only permitted
                    220: within literal contexts.
                    221: If the first character of a text line is a space, that line is printed
                    222: with a leading newline.
                    223: .Ss Scaling Widths
                    224: Many requests and macros support scaled widths for their arguments.
                    225: The syntax for a scaled width is
                    226: .Sq Li [+-]?[0-9]*.[0-9]*[:unit:] ,
                    227: where a decimal must be preceded or followed by at least one digit.
                    228: Negative numbers, while accepted, are truncated to zero.
                    229: .Pp
                    230: The following scaling units are accepted:
                    231: .Pp
                    232: .Bl -tag -width Ds -offset indent -compact
                    233: .It c
                    234: centimetre
                    235: .It i
                    236: inch
                    237: .It P
                    238: pica (~1/6 inch)
                    239: .It p
                    240: point (~1/72 inch)
                    241: .It f
1.56      kristaps  242: scale
1.33      schwarze  243: .Sq u
1.56      kristaps  244: by 65536
1.33      schwarze  245: .It v
                    246: default vertical span
                    247: .It m
                    248: width of rendered
                    249: .Sq m
                    250: .Pq em
                    251: character
                    252: .It n
                    253: width of rendered
                    254: .Sq n
                    255: .Pq en
                    256: character
                    257: .It u
1.56      kristaps  258: default horizontal span for the terminal
1.33      schwarze  259: .It M
                    260: mini-em (~1/100 em)
                    261: .El
                    262: .Pp
                    263: Using anything other than
                    264: .Sq m ,
                    265: .Sq n ,
                    266: or
                    267: .Sq v
                    268: is necessarily non-portable across output media.
                    269: See
                    270: .Sx COMPATIBILITY .
                    271: .Pp
                    272: If a scaling unit is not provided, the numerical value is interpreted
                    273: under the default rules of
                    274: .Sq v
                    275: for vertical spaces and
                    276: .Sq u
                    277: for horizontal ones.
                    278: .Pp
                    279: Examples:
                    280: .Bl -tag -width ".Bl -tag -width 2i" -offset indent -compact
                    281: .It Li \&.Bl -tag -width 2i
                    282: two-inch tagged list indentation in
                    283: .Xr mdoc 7
                    284: .It Li \&.HP 2i
                    285: two-inch tagged list indentation in
                    286: .Xr man 7
                    287: .It Li \&.sp 2v
                    288: two vertical spaces
                    289: .El
                    290: .Ss Sentence Spacing
                    291: Each sentence should terminate at the end of an input line.
                    292: By doing this, a formatter will be able to apply the proper amount of
                    293: spacing after the end of sentence (unescaped) period, exclamation mark,
                    294: or question mark followed by zero or more non-sentence closing
                    295: delimiters
                    296: .Po
                    297: .Sq \&) ,
                    298: .Sq \&] ,
                    299: .Sq \&' ,
                    300: .Sq \&"
                    301: .Pc .
                    302: .Pp
                    303: The proper spacing is also intelligently preserved if a sentence ends at
                    304: the boundary of a macro line.
                    305: .Pp
                    306: Examples:
                    307: .Bd -literal -offset indent -compact
                    308: Do not end sentences mid-line like this.  Instead,
                    309: end a sentence like this.
                    310: A macro would end like this:
                    311: \&.Xr mandoc 1 \&.
                    312: .Ed
1.17      schwarze  313: .Sh REQUEST SYNTAX
                    314: A request or macro line consists of:
                    315: .Pp
                    316: .Bl -enum -compact
                    317: .It
                    318: the control character
                    319: .Sq \&.
1.1       kristaps  320: or
1.17      schwarze  321: .Sq \(aq
                    322: at the beginning of the line,
                    323: .It
                    324: optionally an arbitrary amount of whitespace,
                    325: .It
                    326: the name of the request or the macro, which is one word of arbitrary
                    327: length, terminated by whitespace,
                    328: .It
                    329: and zero or more arguments delimited by whitespace.
                    330: .El
                    331: .Pp
                    332: Thus, the following request lines are all equivalent:
1.1       kristaps  333: .Bd -literal -offset indent
1.17      schwarze  334: \&.ig end
                    335: \&.ig    end
                    336: \&.   ig end
1.1       kristaps  337: .Ed
1.24      schwarze  338: .Sh MACRO SYNTAX
1.33      schwarze  339: Macros are provided by the
                    340: .Xr mdoc 7
                    341: and
                    342: .Xr man 7
                    343: languages and can be defined by the
1.24      schwarze  344: .Sx \&de
                    345: request.
                    346: When called, they follow the same syntax as requests, except that
                    347: macro arguments may optionally be quoted by enclosing them
                    348: in double quote characters
                    349: .Pq Sq \(dq .
1.33      schwarze  350: Quoted text, even if it contains whitespace or would cause
                    351: a macro invocation when unquoted, is always considered literal text.
                    352: Inside quoted text, pairs of double quote characters
                    353: .Pq Sq Qq
                    354: resolve to single double quote characters.
                    355: .Pp
1.32      kristaps  356: To be recognised as the beginning of a quoted argument, the opening
1.24      schwarze  357: quote character must be preceded by a space character.
                    358: A quoted argument extends to the next double quote character that is not
                    359: part of a pair, or to the end of the input line, whichever comes earlier.
                    360: Leaving out the terminating double quote character at the end of the line
                    361: is discouraged.
                    362: For clarity, if more arguments follow on the same input line,
                    363: it is recommended to follow the terminating double quote character
                    364: by a space character; in case the next character after the terminating
                    365: double quote character is anything else, it is regarded as the beginning
                    366: of the next, unquoted argument.
                    367: .Pp
                    368: Both in quoted and unquoted arguments, pairs of backslashes
                    369: .Pq Sq \e\e
                    370: resolve to single backslashes.
                    371: In unquoted arguments, space characters can alternatively be included
                    372: by preceding them with a backslash
                    373: .Pq Sq \e\~ ,
                    374: but quoting is usually better for clarity.
1.33      schwarze  375: .Pp
                    376: Examples:
                    377: .Bl -tag -width Ds -offset indent -compact
                    378: .It Li .Fn strlen \(dqconst char *s\(dq
                    379: Group arguments
                    380: .Qq const char *s
                    381: into one function argument.
                    382: If unspecified,
                    383: .Qq const ,
                    384: .Qq char ,
                    385: and
                    386: .Qq *s
                    387: would be considered separate arguments.
                    388: .It Li .Op \(dqFl a\(dq
                    389: Consider
                    390: .Qq \&Fl a
                    391: as literal text instead of a flag macro.
                    392: .El
1.15      kristaps  393: .Sh REQUEST REFERENCE
1.17      schwarze  394: The
1.15      kristaps  395: .Xr mandoc 1
                    396: .Nm
1.32      kristaps  397: parser recognises the following requests.
1.63      schwarze  398: For requests marked as "ignored" or "unsupported", any arguments are
                    399: ignored, and the number of arguments is not checked.
                    400: .Ss \&ab
                    401: Abort processing.
                    402: Currently unsupported.
1.15      kristaps  403: .Ss \&ad
                    404: Set line adjustment mode.
1.63      schwarze  405: It takes one argument to select normal, left, right,
                    406: or center adjustment for subsequent text.
                    407: Currently ignored.
                    408: .Ss \&af
                    409: Assign an output format to a number register.
                    410: Currently ignored.
                    411: .Ss \&aln
                    412: Create an alias for a number register.
                    413: Currently unsupported.
                    414: .Ss \&als
                    415: Create an alias for a request, string, macro, or diversion.
                    416: Currently unsupported.
1.3       kristaps  417: .Ss \&am
1.15      kristaps  418: Append to a macro definition.
                    419: The syntax of this request is the same as that of
                    420: .Sx \&de .
1.3       kristaps  421: .Ss \&am1
1.15      kristaps  422: Append to a macro definition, switching roff compatibility mode off
1.63      schwarze  423: during macro execution (groff extension).
1.15      kristaps  424: The syntax of this request is the same as that of
                    425: .Sx \&de1 .
1.55      schwarze  426: Since
                    427: .Xr mandoc 1
                    428: does not implement
                    429: .Nm
                    430: compatibility mode at all, it handles this request as an alias for
                    431: .Sx \&am .
1.63      schwarze  432: .Ss \&ami
                    433: Append to a macro definition, specifying the macro name indirectly
                    434: (groff extension).
                    435: The syntax of this request is the same as that of
                    436: .Sx \&dei .
                    437: .Ss \&ami1
                    438: Append to a macro definition, specifying the macro name indirectly
                    439: and switching roff compatibility mode off during macro execution
                    440: (groff extension).
                    441: The syntax of this request is the same as that of
                    442: .Sx \&dei1 .
                    443: Since
                    444: .Xr mandoc 1
                    445: does not implement
                    446: .Nm
                    447: compatibility mode at all, it handles this request as an alias for
                    448: .Sx \&ami .
1.47      schwarze  449: .Ss \&as
                    450: Append to a user-defined string.
                    451: The syntax of this request is the same as that of
                    452: .Sx \&ds .
                    453: If a user-defined string with the specified name does not yet exist,
                    454: it is set to the empty string before appending.
1.63      schwarze  455: .Ss \&as1
                    456: Append to a user-defined string, switching roff compatibility mode off
                    457: during macro execution (groff extension).
                    458: The syntax of this request is the same as that of
                    459: .Sx \&ds1 .
                    460: Since
                    461: .Xr mandoc 1
                    462: does not implement
                    463: .Nm
                    464: compatibility mode at all, it handles this request as an alias for
                    465: .Sx \&as .
                    466: .Ss \&asciify
                    467: Fully unformat a diversion.
                    468: Currently unsupported.
                    469: .Ss \&backtrace
                    470: Print a backtrace of the input stack.
                    471: This is a groff extension and currently ignored.
                    472: .Ss \&bd
                    473: Artificially embolden by repeated printing with small shifts.
                    474: Currently ignored.
                    475: .Ss \&bleedat
                    476: Set the BleedBox page parameter for PDF generation.
                    477: This is a Heirloom extension and currently ignored.
                    478: .Ss \&blm
                    479: Set a blank line trap.
                    480: Currently unsupported.
                    481: .Ss \&box
                    482: Begin a diversion without including a partially filled line.
                    483: Currently unsupported.
                    484: .Ss \&boxa
                    485: Add to a diversion without including a partially filled line.
                    486: Currently unsupported.
                    487: .Ss \&bp
                    488: Begin new page.
                    489: Currently ignored.
                    490: .Ss \&BP
                    491: Define a frame and place a picture in it.
                    492: This is a Heirloom extension and currently unsupported.
                    493: .Ss \&br
                    494: Break the output line.
                    495: See
                    496: .Xr man 7
                    497: and
                    498: .Xr mdoc 7 .
                    499: .Ss \&break
                    500: Break out of a
                    501: .Sx \&while
                    502: loop.
                    503: Currently unsupported.
                    504: .Ss \&breakchar
                    505: Optional line break characters.
                    506: This is a Heirloom extension and currently ignored.
                    507: .Ss \&brnl
                    508: Break output line after next N input lines.
                    509: This is a Heirloom extension and currently ignored.
                    510: .Ss \&brp
                    511: Break and spread output line.
                    512: Currently, this is implemented as an alias for
                    513: .Sx \&br .
                    514: .Ss \&brpnl
                    515: Break and spread output line after next N input lines.
                    516: This is a Heirloom extension and currently ignored.
                    517: .Ss \&c2
                    518: Change the no-break control character.
                    519: Currently unsupported.
1.39      kristaps  520: .Ss \&cc
1.63      schwarze  521: Change the control character.
1.39      kristaps  522: Its syntax is as follows:
                    523: .Bd -literal -offset indent
                    524: .Pf . Cm \&cc Op Ar c
                    525: .Ed
                    526: .Pp
                    527: If
                    528: .Ar c
                    529: is not specified, the control character is reset to
                    530: .Sq \&. .
                    531: Trailing characters are ignored.
1.47      schwarze  532: .Ss \&ce
                    533: Center some lines.
1.63      schwarze  534: It takes one integer argument, specifying how many lines to center.
                    535: Currently ignored.
                    536: .Ss \&cf
                    537: Output the contents of a file.
                    538: Ignored because insecure.
                    539: .Ss \&cflags
                    540: Set character flags.
                    541: This is a groff extension and currently ignored.
                    542: .Ss \&ch
                    543: Change a trap location.
                    544: Currently ignored.
                    545: .Ss \&char
                    546: Define a new glyph.
                    547: Currently unsupported.
                    548: .Ss \&chop
                    549: Remove the last character from a macro, string, or diversion.
                    550: Currently unsupported.
                    551: .Ss \&class
                    552: Define a character class.
                    553: This is a groff extension and currently ignored.
                    554: .Ss \&close
                    555: Close an open file.
                    556: Ignored because insecure.
                    557: .Ss \&CL
                    558: Print text in color.
                    559: This is a Heirloom extension and currently unsupported.
                    560: .Ss \&color
                    561: Activate or deactivate colors.
                    562: This is a groff extension and currently ignored.
                    563: .Ss \&composite
                    564: Define a name component for composite glyph names.
                    565: This is a groff extension and currently unsupported.
                    566: .Ss \&continue
                    567: Immediately start the next iteration of a
                    568: .Sx \&while
                    569: loop.
                    570: Currently unsupported.
                    571: .Ss \&cp
                    572: Switch
                    573: .Nm
                    574: compatibility mode on or off.
                    575: Currently ignored.
                    576: .Ss \&cropat
                    577: Set the CropBox page parameter for PDF generation.
                    578: This is a Heirloom extension and currently ignored.
                    579: .Ss \&cs
                    580: Constant character spacing mode.
                    581: Currently ignored.
                    582: .Ss \&cu
                    583: Underline including whitespace.
                    584: Currently ignored.
                    585: .Ss \&da
                    586: Append to a diversion.
                    587: Currently unsupported.
                    588: .Ss \&dch
                    589: Change a trap location in the current diversion.
                    590: This is a Heirloom extension and currently unsupported.
1.3       kristaps  591: .Ss \&de
1.17      schwarze  592: Define a
1.15      kristaps  593: .Nm
                    594: macro.
                    595: Its syntax can be either
                    596: .Bd -literal -offset indent
                    597: .Pf . Cm \&de Ar name
                    598: .Ar macro definition
                    599: \&..
                    600: .Ed
                    601: .Pp
                    602: or
                    603: .Bd -literal -offset indent
                    604: .Pf . Cm \&de Ar name Ar end
                    605: .Ar macro definition
                    606: .Pf . Ar end
                    607: .Ed
                    608: .Pp
                    609: Both forms define or redefine the macro
                    610: .Ar name
                    611: to represent the
                    612: .Ar macro definition ,
                    613: which may consist of one or more input lines, including the newline
                    614: characters terminating each line, optionally containing calls to
                    615: .Nm
                    616: requests,
                    617: .Nm
                    618: macros or high-level macros like
                    619: .Xr man 7
                    620: or
                    621: .Xr mdoc 7
                    622: macros, whichever applies to the document in question.
                    623: .Pp
                    624: Specifying a custom
                    625: .Ar end
                    626: macro works in the same way as for
                    627: .Sx \&ig ;
                    628: namely, the call to
                    629: .Sq Pf . Ar end
                    630: first ends the
                    631: .Ar macro definition ,
                    632: and after that, it is also evaluated as a
                    633: .Nm
                    634: request or
                    635: .Nm
                    636: macro, but not as a high-level macro.
                    637: .Pp
1.17      schwarze  638: The macro can be invoked later using the syntax
1.15      kristaps  639: .Pp
                    640: .D1 Pf . Ar name Op Ar argument Op Ar argument ...
                    641: .Pp
1.24      schwarze  642: Regarding argument parsing, see
                    643: .Sx MACRO SYNTAX
                    644: above.
1.15      kristaps  645: .Pp
1.17      schwarze  646: The line invoking the macro will be replaced
1.15      kristaps  647: in the input stream by the
                    648: .Ar macro definition ,
                    649: replacing all occurrences of
                    650: .No \e\e$ Ns Ar N ,
1.17      schwarze  651: where
1.15      kristaps  652: .Ar N
                    653: is a digit, by the
                    654: .Ar N Ns th Ar argument .
                    655: For example,
                    656: .Bd -literal -offset indent
                    657: \&.de ZN
                    658: \efI\e^\e\e$1\e^\efP\e\e$2
                    659: \&..
                    660: \&.ZN XtFree .
                    661: .Ed
                    662: .Pp
                    663: produces
                    664: .Pp
                    665: .D1 \efI\e^XtFree\e^\efP.
                    666: .Pp
                    667: in the input stream, and thus in the output: \fI\^XtFree\^\fP.
1.73      schwarze  668: Each occurrence of \e\e$* is replaced with all the arguments,
                    669: joined together with single blank characters.
1.15      kristaps  670: .Pp
1.17      schwarze  671: Since macros and user-defined strings share a common string table,
1.15      kristaps  672: defining a macro
                    673: .Ar name
                    674: clobbers the user-defined string
                    675: .Ar name ,
                    676: and the
                    677: .Ar macro definition
                    678: can also be printed using the
                    679: .Sq \e*
                    680: string interpolation syntax described below
                    681: .Sx ds ,
                    682: but this is rarely useful because every macro definition contains at least
                    683: one explicit newline character.
1.16      schwarze  684: .Pp
                    685: In order to prevent endless recursion, both groff and
                    686: .Xr mandoc 1
                    687: limit the stack depth for expanding macros and strings
1.61      schwarze  688: to a large, but finite number, and
                    689: .Xr mandoc 1
                    690: also limits the length of the expanded input line.
                    691: Do not rely on the exact values of these limits.
1.63      schwarze  692: .Ss \&de1
                    693: Define a
                    694: .Nm
                    695: macro that will be executed with
                    696: .Nm
                    697: compatibility mode switched off during macro execution.
                    698: This is a groff extension.
                    699: Since
                    700: .Xr mandoc 1
                    701: does not implement
                    702: .Nm
                    703: compatibility mode at all, it handles this request as an alias for
                    704: .Sx \&de .
                    705: .Ss \&defcolor
                    706: Define a color name.
                    707: This is a groff extension and currently ignored.
1.3       kristaps  708: .Ss \&dei
1.17      schwarze  709: Define a
1.15      kristaps  710: .Nm
1.63      schwarze  711: macro, specifying the macro name indirectly (groff extension).
1.17      schwarze  712: The syntax of this request is the same as that of
1.15      kristaps  713: .Sx \&de .
1.55      schwarze  714: The request
                    715: .Pp
                    716: .D1 Pf . Cm \&dei Ar name Op Ar end
                    717: .Pp
                    718: has the same effect as:
                    719: .Pp
                    720: .D1 Pf . Cm \&de No \e* Ns Bo Ar name Bc Op \e* Ns Bq Ar end
1.63      schwarze  721: .Ss \&dei1
1.17      schwarze  722: Define a
1.15      kristaps  723: .Nm
                    724: macro that will be executed with
                    725: .Nm
1.63      schwarze  726: compatibility mode switched off during macro execution,
                    727: specifying the macro name indirectly (groff extension).
1.15      kristaps  728: Since
                    729: .Xr mandoc 1
                    730: does not implement
                    731: .Nm
1.17      schwarze  732: compatibility mode at all, it handles this request as an alias for
1.63      schwarze  733: .Sx \&dei .
                    734: .Ss \&device
                    735: This request only makes sense with the groff-specific intermediate
                    736: output format and is unsupported.
                    737: .Ss \&devicem
                    738: This request only makes sense with the groff-specific intermediate
                    739: output format and is unsupported.
                    740: .Ss \&di
                    741: Begin a diversion.
                    742: Currently unsupported.
                    743: .Ss \&do
                    744: Execute
                    745: .Nm
                    746: request or macro line with compatibility mode disabled.
                    747: Currently unsupported.
1.6       schwarze  748: .Ss \&ds
1.15      kristaps  749: Define a user-defined string.
1.13      kristaps  750: Its syntax is as follows:
                    751: .Pp
1.15      kristaps  752: .D1 Pf . Cm \&ds Ar name Oo \(dq Oc Ns Ar string
1.13      kristaps  753: .Pp
                    754: The
1.15      kristaps  755: .Ar name
1.13      kristaps  756: and
1.15      kristaps  757: .Ar string
                    758: arguments are space-separated.
                    759: If the
                    760: .Ar string
                    761: begins with a double-quote character, that character will not be part
                    762: of the string.
                    763: All remaining characters on the input line form the
                    764: .Ar string ,
                    765: including whitespace and double-quote characters, even trailing ones.
                    766: .Pp
1.13      kristaps  767: The
1.15      kristaps  768: .Ar string
                    769: can be interpolated into subsequent text by using
                    770: .No \e* Ns Bq Ar name
                    771: for a
                    772: .Ar name
                    773: of arbitrary length, or \e*(NN or \e*N if the length of
                    774: .Ar name
                    775: is two or one characters, respectively.
1.17      schwarze  776: Interpolation can be prevented by escaping the leading backslash;
                    777: that is, an asterisk preceded by an even number of backslashes
                    778: does not trigger string interpolation.
1.15      kristaps  779: .Pp
                    780: Since user-defined strings and macros share a common string table,
                    781: defining a string
                    782: .Ar name
1.17      schwarze  783: clobbers the macro
1.15      kristaps  784: .Ar name ,
                    785: and the
                    786: .Ar name
                    787: used for defining a string can also be invoked as a macro,
                    788: in which case the following input line will be appended to the
                    789: .Ar string ,
                    790: forming a new input line passed to the
                    791: .Nm
                    792: parser.
                    793: For example,
                    794: .Bd -literal -offset indent
                    795: \&.ds badidea .S
                    796: \&.badidea
                    797: H SYNOPSIS
                    798: .Ed
                    799: .Pp
                    800: invokes the
                    801: .Cm SH
                    802: macro when used in a
                    803: .Xr man 7
                    804: document.
                    805: Such abuse is of course strongly discouraged.
1.63      schwarze  806: .Ss \&ds1
                    807: Define a user-defined string that will be expanded with
                    808: .Nm
                    809: compatibility mode switched off during string expansion.
                    810: This is a groff extension.
                    811: Since
                    812: .Xr mandoc 1
                    813: does not implement
                    814: .Nm
                    815: compatibility mode at all, it handles this request as an alias for
                    816: .Sx \&ds .
                    817: .Ss \&dwh
                    818: Set a location trap in the current diversion.
                    819: This is a Heirloom extension and currently unsupported.
                    820: .Ss \&dt
                    821: Set a trap within a diversion.
                    822: Currently unsupported.
                    823: .Ss \&ec
                    824: Change the escape character.
                    825: Currently unsupported.
                    826: .Ss \&ecs
                    827: Restore the escape character.
                    828: Currently unsupported.
                    829: .Ss \&ecr
                    830: Save the escape character.
                    831: Currently unsupported.
1.5       kristaps  832: .Ss \&el
                    833: The
                    834: .Qq else
                    835: half of an if/else conditional.
                    836: Pops a result off the stack of conditional evaluations pushed by
                    837: .Sx \&ie
                    838: and uses it as its conditional.
                    839: If no stack entries are present (e.g., due to no prior
                    840: .Sx \&ie
                    841: calls)
                    842: then false is assumed.
1.17      schwarze  843: The syntax of this request is similar to
1.5       kristaps  844: .Sx \&if
                    845: except that the conditional is missing.
1.63      schwarze  846: .Ss \&em
                    847: Set a trap at the end of input.
                    848: Currently unsupported.
1.27      kristaps  849: .Ss \&EN
                    850: End an equation block.
                    851: See
                    852: .Sx \&EQ .
1.63      schwarze  853: .Ss \&eo
                    854: Disable the escape mechanism completely.
                    855: Currently unsupported.
                    856: .Ss \&EP
                    857: End a picture started by
                    858: .Sx \&BP .
                    859: This is a Heirloom extension and currently unsupported.
1.27      kristaps  860: .Ss \&EQ
                    861: Begin an equation block.
                    862: See
                    863: .Xr eqn 7
                    864: for a description of the equation language.
1.63      schwarze  865: .Ss \&errprint
                    866: Print a string like an error message.
                    867: This is a Heirloom extension and currently ignored.
                    868: .Ss \&ev
                    869: Switch to another environment.
                    870: Currently unsupported.
                    871: .Ss \&evc
                    872: Copy an environment into the current environment.
                    873: Currently unsupported.
                    874: .Ss \&ex
                    875: Abort processing and exit.
                    876: Currently unsupported.
                    877: .Ss \&fallback
                    878: Select the fallback sequence for a font.
                    879: This is a Heirloom extension and currently ignored.
1.43      schwarze  880: .Ss \&fam
                    881: Change the font family.
1.63      schwarze  882: Takes one argument specifying the font family to be selected.
                    883: It is a groff extension and currently ignored.
                    884: .Ss \&fc
                    885: Define a delimiting and a padding character for fields.
                    886: Currently unsupported.
                    887: .Ss \&fchar
                    888: Define a fallback glyph.
                    889: Currently unsupported.
                    890: .Ss \&fcolor
                    891: Set the fill color for \eD objects.
                    892: This is a groff extension and currently ignored.
                    893: .Ss \&fdeferlig
                    894: Defer ligature building.
                    895: This is a Heirloom extension and currently ignored.
                    896: .Ss \&feature
                    897: Enable or disable an OpenType feature.
                    898: This is a Heirloom extension and currently ignored.
                    899: .Ss \&fi
                    900: Switch to fill mode.
                    901: See
                    902: .Xr man 7 .
                    903: Ignored in
                    904: .Xr mdoc 7 .
                    905: .Ss \&fkern
                    906: Control the use of kerning tables for a font.
                    907: This is a Heirloom extension and currently ignored.
                    908: .Ss \&fl
                    909: Flush output.
                    910: Currently ignored.
                    911: .Ss \&flig
                    912: Define ligatures.
                    913: This is a Heirloom extension and currently ignored.
                    914: .Ss \&fp
                    915: Assign font position.
                    916: Currently ignored.
                    917: .Ss \&fps
                    918: Mount a font with a special character map.
                    919: This is a Heirloom extension and currently ignored.
                    920: .Ss \&fschar
                    921: Define a font-specific fallback glyph.
                    922: This is a groff extension and currently unsupported.
                    923: .Ss \&fspacewidth
                    924: Set a font-specific width for the space character.
                    925: This is a Heirloom extension and currently ignored.
                    926: .Ss \&fspecial
                    927: Conditionally define a special font.
                    928: This is a groff extension and currently ignored.
1.49      schwarze  929: .Ss \&ft
                    930: Change the font.
                    931: Its syntax is as follows:
                    932: .Pp
                    933: .D1 Pf . Cm \&ft Op Ar font
                    934: .Pp
                    935: The following
                    936: .Ar font
                    937: arguments are supported:
                    938: .Bl -tag -width 4n -offset indent
                    939: .It Cm B , BI , 3 , 4
                    940: switches to
                    941: .Sy bold
                    942: font
                    943: .It Cm I , 2
                    944: switches to
                    945: .Em underlined
                    946: font
                    947: .It Cm R , CW , 1
                    948: switches to normal font
                    949: .It Cm P No "or no argument"
                    950: switches back to the previous font
                    951: .El
                    952: .Pp
                    953: This request takes effect only locally, may be overridden by macros
                    954: and escape sequences, and is only supported in
                    955: .Xr man 7
                    956: for now.
1.63      schwarze  957: .Ss \&ftr
                    958: Translate font name.
                    959: This is a groff extension and currently ignored.
                    960: .Ss \&fzoom
                    961: Zoom font size.
                    962: Currently ignored.
                    963: .Ss \&gcolor
                    964: Set glyph color.
                    965: This is a groff extension and currently ignored.
                    966: .Ss \&hc
                    967: Set the hyphenation character.
                    968: Currently ignored.
                    969: .Ss \&hcode
                    970: Set hyphenation codes of characters.
                    971: Currently ignored.
                    972: .Ss \&hidechar
                    973: Hide characters in a font.
                    974: This is a Heirloom extension and currently ignored.
                    975: .Ss \&hla
                    976: Set hyphenation language.
                    977: This is a groff extension and currently ignored.
                    978: .Ss \&hlm
                    979: Set maximum number of consecutive hyphenated lines.
                    980: Currently ignored.
                    981: .Ss \&hpf
                    982: Load hyphenation pattern file.
                    983: This is a groff extension and currently ignored.
                    984: .Ss \&hpfa
                    985: Load hyphenation pattern file, appending to the current patterns.
                    986: This is a groff extension and currently ignored.
                    987: .Ss \&hpfcode
                    988: Define mapping values for character codes in hyphenation patterns.
                    989: This is a groff extension and currently ignored.
1.44      schwarze  990: .Ss \&hw
                    991: Specify hyphenation points in words.
1.63      schwarze  992: Currently ignored.
1.15      kristaps  993: .Ss \&hy
                    994: Set automatic hyphenation mode.
1.63      schwarze  995: Currently ignored.
                    996: .Ss \&hylang
                    997: Set hyphenation language.
                    998: This is a Heirloom extension and currently ignored.
                    999: .Ss \&hylen
                   1000: Minimum word length for hyphenation.
                   1001: This is a Heirloom extension and currently ignored.
                   1002: .Ss \&hym
                   1003: Set hyphenation margin.
                   1004: This is a groff extension and currently ignored.
                   1005: .Ss \&hypp
                   1006: Define hyphenation penalties.
                   1007: This is a Heirloom extension and currently ignored.
1.64      schwarze 1008: .Ss \&hys
1.63      schwarze 1009: Set hyphenation space.
                   1010: This is a groff extension and currently ignored.
1.5       kristaps 1011: .Ss \&ie
                   1012: The
                   1013: .Qq if
                   1014: half of an if/else conditional.
                   1015: The result of the conditional is pushed into a stack used by subsequent
                   1016: invocations of
                   1017: .Sx \&el ,
                   1018: which may be separated by any intervening input (or not exist at all).
                   1019: Its syntax is equivalent to
                   1020: .Sx \&if .
1.1       kristaps 1021: .Ss \&if
1.7       schwarze 1022: Begins a conditional.
1.48      schwarze 1023: This request has the following syntax:
                   1024: .Bd -literal -offset indent
                   1025: \&.if COND BODY
                   1026: .Ed
                   1027: .Bd -literal -offset indent
                   1028: \&.if COND \e{BODY
                   1029: BODY...\e}
                   1030: .Ed
                   1031: .Bd -literal -offset indent
                   1032: \&.if COND \e{\e
                   1033: BODY...
                   1034: \&.\e}
                   1035: .Ed
                   1036: .Pp
                   1037: COND is a conditional statement.
                   1038: Currently,
                   1039: .Xr mandoc 1
                   1040: supports the following subset of roff conditionals:
                   1041: .Bl -bullet
                   1042: .It
                   1043: If
                   1044: .Sq \&!
                   1045: is prefixed to COND, the condition is logically inverted.
                   1046: .It
                   1047: If the first character of COND is
                   1048: .Sq n
                   1049: .Pq nroff mode
                   1050: or
                   1051: .Sq o
                   1052: .Pq odd page ,
                   1053: COND evaluates to true.
                   1054: .It
                   1055: If the first character of COND is
                   1056: .Sq c
                   1057: .Pq character available ,
                   1058: .Sq d
                   1059: .Pq string defined ,
                   1060: .Sq e
                   1061: .Pq even page ,
                   1062: .Sq t
                   1063: .Pq troff mode ,
1.59      schwarze 1064: or
                   1065: .Sq v
                   1066: .Pq vroff mode ,
1.48      schwarze 1067: COND evaluates to false.
1.72      schwarze 1068: .It
                   1069: If the first character of COND is
                   1070: .Sq r ,
1.75      schwarze 1071: it evaluates to true if the rest of COND is the name of an existing
1.72      schwarze 1072: number register; otherwise, it evaluates to false.
1.48      schwarze 1073: .It
1.53      schwarze 1074: If COND starts with a parenthesis or with an optionally signed
                   1075: integer number, it is evaluated according to the rules of
                   1076: .Sx Numerical expressions
                   1077: explained below.
1.57      schwarze 1078: It evaluates to true if the result is positive,
1.53      schwarze 1079: or to false if the result is zero or negative.
1.48      schwarze 1080: .It
                   1081: Otherwise, the first character of COND is regarded as a delimiter
                   1082: and COND evaluates to true if the string extending from its first
                   1083: to its second occurrence is equal to the string extending from its
                   1084: second to its third occurrence.
                   1085: .It
                   1086: If COND cannot be parsed, it evaluates to false.
                   1087: .El
                   1088: .Pp
1.3       kristaps 1089: If a conditional is false, its children are not processed, but are
                   1090: syntactically interpreted to preserve the integrity of the input
                   1091: document.
                   1092: Thus,
                   1093: .Pp
1.17      schwarze 1094: .D1 \&.if t .ig
1.3       kristaps 1095: .Pp
                   1096: will discard the
                   1097: .Sq \&.ig ,
                   1098: which may lead to interesting results, but
                   1099: .Pp
1.17      schwarze 1100: .D1 \&.if t .if t \e{\e
1.3       kristaps 1101: .Pp
                   1102: will continue to syntactically interpret to the block close of the final
                   1103: conditional.
                   1104: Sub-conditionals, in this case, obviously inherit the truth value of
                   1105: the parent.
1.1       kristaps 1106: .Pp
                   1107: If the BODY section is begun by an escaped brace
                   1108: .Sq \e{ ,
1.48      schwarze 1109: scope continues until the end of the input line containing the
                   1110: matching closing-brace escape sequence
                   1111: .Sq \e} .
1.17      schwarze 1112: If the BODY is not enclosed in braces, scope continues until
                   1113: the end of the line.
1.1       kristaps 1114: If the COND is followed by a BODY on the same line, whether after a
1.17      schwarze 1115: brace or not, then requests and macros
1.1       kristaps 1116: .Em must
                   1117: begin with a control character.
                   1118: It is generally more intuitive, in this case, to write
                   1119: .Bd -literal -offset indent
                   1120: \&.if COND \e{\e
                   1121: \&.foo
                   1122: bar
                   1123: \&.\e}
                   1124: .Ed
                   1125: .Pp
1.17      schwarze 1126: than having the request or macro follow as
1.1       kristaps 1127: .Pp
                   1128: .D1 \&.if COND \e{ .foo
                   1129: .Pp
                   1130: The scope of a conditional is always parsed, but only executed if the
                   1131: conditional evaluates to true.
                   1132: .Pp
1.29      kristaps 1133: Note that the
1.1       kristaps 1134: .Sq \e}
1.29      kristaps 1135: is converted into a zero-width escape sequence if not passed as a
                   1136: standalone macro
                   1137: .Sq \&.\e} .
                   1138: For example,
                   1139: .Pp
                   1140: .D1 \&.Fl a \e} b
                   1141: .Pp
                   1142: will result in
1.8       kristaps 1143: .Sq \e}
1.29      kristaps 1144: being considered an argument of the
                   1145: .Sq \&Fl
                   1146: macro.
1.1       kristaps 1147: .Ss \&ig
1.2       kristaps 1148: Ignore input.
1.15      kristaps 1149: Its syntax can be either
                   1150: .Bd -literal -offset indent
                   1151: .Pf . Cm \&ig
                   1152: .Ar ignored text
1.2       kristaps 1153: \&..
                   1154: .Ed
1.15      kristaps 1155: .Pp
                   1156: or
                   1157: .Bd -literal -offset indent
                   1158: .Pf . Cm \&ig Ar end
                   1159: .Ar ignored text
                   1160: .Pf . Ar end
1.2       kristaps 1161: .Ed
                   1162: .Pp
                   1163: In the first case, input is ignored until a
                   1164: .Sq \&..
1.17      schwarze 1165: request is encountered on its own line.
1.15      kristaps 1166: In the second case, input is ignored until the specified
                   1167: .Sq Pf . Ar end
                   1168: macro is encountered.
                   1169: Do not use the escape character
1.2       kristaps 1170: .Sq \e
1.15      kristaps 1171: anywhere in the definition of
                   1172: .Ar end ;
                   1173: it would cause very strange behaviour.
                   1174: .Pp
                   1175: When the
                   1176: .Ar end
                   1177: macro is a roff request or a roff macro, like in
1.2       kristaps 1178: .Pp
                   1179: .D1 \&.ig if
                   1180: .Pp
                   1181: the subsequent invocation of
                   1182: .Sx \&if
1.15      kristaps 1183: will first terminate the
                   1184: .Ar ignored text ,
                   1185: then be invoked as usual.
                   1186: Otherwise, it only terminates the
                   1187: .Ar ignored text ,
                   1188: and arguments following it or the
                   1189: .Sq \&..
1.17      schwarze 1190: request are discarded.
1.63      schwarze 1191: .Ss \&in
                   1192: Change indentation.
                   1193: See
                   1194: .Xr man 7 .
                   1195: Ignored in
                   1196: .Xr mdoc 7 .
                   1197: .Ss \&index
                   1198: Find a substring in a string.
                   1199: This is a Heirloom extension and currently unsupported.
                   1200: .Ss \&it
                   1201: Set an input line trap.
                   1202: Its syntax is as follows:
                   1203: .Pp
1.70      schwarze 1204: .D1 Pf . Cm it Ar expression macro
1.63      schwarze 1205: .Pp
                   1206: The named
                   1207: .Ar macro
1.70      schwarze 1208: will be invoked after processing the number of input text lines
                   1209: specified by the numerical
                   1210: .Ar expression .
                   1211: While evaluating the
                   1212: .Ar expression ,
                   1213: the unit suffixes described below
                   1214: .Sx Scaling Widths
                   1215: are ignored.
1.63      schwarze 1216: .Ss \&itc
                   1217: Set an input line trap, not counting lines ending with \ec.
                   1218: Currently unsupported.
                   1219: .Ss \&IX
                   1220: To support the generation of a table of contents,
                   1221: .Xr pod2man 1
                   1222: emits this user-defined macro, usually without defining it.
                   1223: To avoid reporting large numbers of spurious errors,
                   1224: .Xr mandoc 1
                   1225: ignores it.
                   1226: .Ss \&kern
                   1227: Switch kerning on or off.
                   1228: Currently ignored.
                   1229: .Ss \&kernafter
                   1230: Increase kerning after some characters.
                   1231: This is a Heirloom extension and currently ignored.
                   1232: .Ss \&kernbefore
                   1233: Increase kerning before some characters.
                   1234: This is a Heirloom extension and currently ignored.
                   1235: .Ss \&kernpair
                   1236: Add a kerning pair to the kerning table.
                   1237: This is a Heirloom extension and currently ignored.
                   1238: .Ss \&lc
                   1239: Define a leader repetition character.
                   1240: Currently unsupported.
                   1241: .Ss \&lc_ctype
                   1242: Set the
                   1243: .Dv LC_CTYPE
                   1244: locale.
                   1245: This is a Heirloom extension and currently unsupported.
                   1246: .Ss \&lds
                   1247: Define a local string.
                   1248: This is a Heirloom extension and currently unsupported.
                   1249: .Ss \&length
                   1250: Count the number of input characters in a user-defined string.
                   1251: Currently unsupported.
                   1252: .Ss \&letadj
                   1253: Dynamic letter spacing and reshaping.
                   1254: This is a Heirloom extension and currently ignored.
                   1255: .Ss \&lf
                   1256: Change the line number for error messages.
                   1257: Ignored because insecure.
                   1258: .Ss \&lg
                   1259: Switch the ligature mechanism on or off.
                   1260: Currently ignored.
                   1261: .Ss \&lhang
                   1262: Hang characters at left margin.
                   1263: This is a Heirloom extension and currently ignored.
                   1264: .Ss \&linetabs
                   1265: Enable or disable line-tabs mode.
                   1266: This is a groff extension and currently unsupported.
1.50      schwarze 1267: .Ss \&ll
                   1268: Change the output line length.
                   1269: Its syntax is as follows:
                   1270: .Pp
1.51      schwarze 1271: .D1 Pf . Cm \&ll Op Oo +|- Oc Ns Ar width
1.50      schwarze 1272: .Pp
                   1273: If the
                   1274: .Ar width
                   1275: argument is omitted, the line length is reset to its previous value.
                   1276: The default setting for terminal output is 78n.
1.51      schwarze 1277: If a sign is given, the line length is added to or subtracted from;
                   1278: otherwise, it is set to the provided value.
1.50      schwarze 1279: Using this request in new manuals is discouraged for several reasons,
                   1280: among others because it overrides the
                   1281: .Xr mandoc 1
                   1282: .Fl O Cm width
                   1283: command line option.
1.63      schwarze 1284: .Ss \&lnr
                   1285: Set local number register.
                   1286: This is a Heirloom extension and currently unsupported.
                   1287: .Ss \&lnrf
                   1288: Set local floating-point register.
                   1289: This is a Heirloom extension and currently unsupported.
                   1290: .Ss \&lpfx
                   1291: Set a line prefix.
                   1292: This is a Heirloom extension and currently unsupported.
                   1293: .Ss \&ls
                   1294: Set line spacing.
                   1295: It takes one integer argument specifying the vertical distance of
                   1296: subsequent output text lines measured in v units.
                   1297: Currently ignored.
                   1298: .Ss \&lsm
                   1299: Set a leading spaces trap.
                   1300: This is a groff extension and currently unsupported.
                   1301: .Ss \&lt
                   1302: Set title line length.
                   1303: Currently ignored.
                   1304: .Ss \&mc
                   1305: Print margin character in the right margin.
                   1306: Currently ignored.
                   1307: .Ss \&mediasize
                   1308: Set the device media size.
                   1309: This is a Heirloom extension and currently ignored.
                   1310: .Ss \&minss
                   1311: Set minimum word space.
                   1312: This is a Heirloom extension and currently ignored.
                   1313: .Ss \&mk
                   1314: Mark vertical position.
                   1315: Currently ignored.
                   1316: .Ss \&mso
                   1317: Load a macro file.
                   1318: Ignored because insecure.
                   1319: .Ss \&na
                   1320: Disable adjusting without changing the adjustment mode.
                   1321: Currently ignored.
1.15      kristaps 1322: .Ss \&ne
                   1323: Declare the need for the specified minimum vertical space
                   1324: before the next trap or the bottom of the page.
1.63      schwarze 1325: Currently ignored.
                   1326: .Ss \&nf
                   1327: Switch to no-fill mode.
                   1328: See
                   1329: .Xr man 7 .
                   1330: Ignored by
1.64      schwarze 1331: .Xr mdoc 7 .
1.15      kristaps 1332: .Ss \&nh
                   1333: Turn off automatic hyphenation mode.
1.63      schwarze 1334: Currently ignored.
                   1335: .Ss \&nhychar
                   1336: Define hyphenation-inhibiting characters.
                   1337: This is a Heirloom extension and currently ignored.
                   1338: .Ss \&nm
                   1339: Print line numbers.
                   1340: Currently unsupported.
                   1341: .Ss \&nn
                   1342: Temporarily turn off line numbering.
                   1343: Currently unsupported.
                   1344: .Ss \&nop
1.75      schwarze 1345: Execute the rest of the input line as a request or macro line.
1.63      schwarze 1346: Currently unsupported.
1.10      kristaps 1347: .Ss \&nr
1.45      schwarze 1348: Define or change a register.
1.10      kristaps 1349: A register is an arbitrary string value that defines some sort of state,
                   1350: which influences parsing and/or formatting.
                   1351: Its syntax is as follows:
                   1352: .Pp
1.53      schwarze 1353: .D1 Pf \. Cm \&nr Ar name Oo +|- Oc Ns Ar expression
1.10      kristaps 1354: .Pp
1.53      schwarze 1355: For the syntax of
                   1356: .Ar expression ,
                   1357: see
                   1358: .Sx Numerical expressions
                   1359: below.
1.46      schwarze 1360: If it is prefixed by a sign, the register will be
1.45      schwarze 1361: incremented or decremented instead of assigned to.
                   1362: .Pp
                   1363: The following register
1.15      kristaps 1364: .Ar name
1.45      schwarze 1365: is handled specially:
1.10      kristaps 1366: .Bl -tag -width Ds
                   1367: .It Cm nS
                   1368: If set to a positive integer value, certain
                   1369: .Xr mdoc 7
1.17      schwarze 1370: macros will behave in the same way as in the
1.10      kristaps 1371: .Em SYNOPSIS
1.11      kristaps 1372: section.
1.17      schwarze 1373: If set to 0, these macros will behave in the same way as outside the
                   1374: .Em SYNOPSIS
                   1375: section, even when called within the
1.10      kristaps 1376: .Em SYNOPSIS
1.17      schwarze 1377: section itself.
                   1378: Note that starting a new
1.11      kristaps 1379: .Xr mdoc 7
1.17      schwarze 1380: section with the
                   1381: .Cm \&Sh
                   1382: macro will reset this register.
1.10      kristaps 1383: .El
1.63      schwarze 1384: .Ss \&nrf
                   1385: Define or change a floating-point register.
                   1386: This is a Heirloom extension and currently unsupported.
                   1387: .Ss \&nroff
                   1388: Force nroff mode.
                   1389: This is a groff extension and currently ignored.
1.26      schwarze 1390: .Ss \&ns
                   1391: Turn on no-space mode.
1.63      schwarze 1392: Currently ignored.
                   1393: .Ss \&nx
                   1394: Abort processing of the current input file and process another one.
                   1395: Ignored because insecure.
                   1396: .Ss \&open
                   1397: Open a file for writing.
                   1398: Ignored because insecure.
                   1399: .Ss \&opena
                   1400: Open a file for appending.
                   1401: Ignored because insecure.
                   1402: .Ss \&os
                   1403: Output saved vertical space.
                   1404: Currently ignored.
                   1405: .Ss \&output
                   1406: Output directly to intermediate output.
                   1407: Not supported.
                   1408: .Ss \&padj
                   1409: Globally control paragraph-at-once adjustment.
                   1410: This is a Heirloom extension and currently ignored.
                   1411: .Ss \&papersize
                   1412: Set the paper size.
                   1413: This is a Heirloom extension and currently ignored.
                   1414: .Ss \&pc
                   1415: Change the page number character.
                   1416: Currently ignored.
                   1417: .Ss \&pev
                   1418: Print environments.
                   1419: This is a groff extension and currently ignored.
                   1420: .Ss \&pi
                   1421: Pipe output to a shell command.
                   1422: Ignored because insecure.
                   1423: .Ss \&PI
                   1424: Low-level request used by
                   1425: .Sx \&BP .
                   1426: This is a Heirloom extension and currently unsupported.
1.58      schwarze 1427: .Ss \&pl
                   1428: Change page length.
1.63      schwarze 1429: Takes one height argument.
                   1430: Currently ignored.
                   1431: .Ss \&pm
                   1432: Print names and sizes of macros, strings, and diversions.
                   1433: Currently ignored.
                   1434: .Ss \&pn
                   1435: Change page number of the next page.
                   1436: Currently ignored.
                   1437: .Ss \&pnr
                   1438: Print all number registers.
                   1439: Currently ignored.
                   1440: .Ss \&po
                   1441: Set horizontal page offset.
                   1442: Currently ignored.
1.26      schwarze 1443: .Ss \&ps
                   1444: Change point size.
1.63      schwarze 1445: Takes one numerical argument.
                   1446: Currently ignored.
                   1447: .Ss \&psbb
                   1448: Retrieve the bounding box of a PostScript file.
                   1449: Currently unsupported.
                   1450: .Ss \&pshape
                   1451: Set a special shape for the current paragraph.
1.68      schwarze 1452: This is a Heirloom extension and currently unsupported.
1.63      schwarze 1453: .Ss \&pso
                   1454: Include output of a shell command.
                   1455: Ignored because insecure.
                   1456: .Ss \&ptr
                   1457: Print the names and positions of all traps.
                   1458: This is a groff extension and currently ignored.
                   1459: .Ss \&pvs
                   1460: Change post-vertical spacing.
                   1461: This is a groff extension and currently ignored.
                   1462: .Ss \&rchar
                   1463: Remove glyph definitions.
                   1464: Currently unsupported.
                   1465: .Ss \&rd
                   1466: Read from standard input.
                   1467: Currently ignored.
                   1468: .Ss \&recursionlimit
                   1469: Set the maximum stack depth for recursive macros.
                   1470: This is a Heirloom extension and currently ignored.
                   1471: .Ss \&return
                   1472: Exit a macro and return to the caller.
                   1473: Currently unsupported.
                   1474: .Ss \&rfschar
                   1475: Remove font-specific fallback glyph definitions.
                   1476: Currently unsupported.
                   1477: .Ss \&rhang
                   1478: Hang characters at right margin.
                   1479: This is a Heirloom extension and currently ignored.
                   1480: .Ss \&rj
                   1481: Justify unfilled text to the right margin.
                   1482: Currently ignored.
1.52      schwarze 1483: .Ss \&rm
                   1484: Remove a request, macro or string.
                   1485: Its syntax is as follows:
                   1486: .Pp
                   1487: .D1 Pf \. Cm \&rm Ar name
1.63      schwarze 1488: .Ss \&rn
                   1489: Rename a request, macro, diversion, or string.
                   1490: Currently unsupported.
                   1491: .Ss \&rnn
                   1492: Rename a number register.
                   1493: Currently unsupported.
1.52      schwarze 1494: .Ss \&rr
                   1495: Remove a register.
                   1496: Its syntax is as follows:
                   1497: .Pp
                   1498: .D1 Pf \. Cm \&rr Ar name
1.63      schwarze 1499: .Ss \&rs
                   1500: End no-space mode.
                   1501: Currently ignored.
                   1502: .Ss \&rt
                   1503: Return to marked vertical position.
                   1504: Currently ignored.
                   1505: .Ss \&schar
                   1506: Define global fallback glyph.
                   1507: This is a groff extension and currently unsupported.
                   1508: .Ss \&sentchar
                   1509: Define sentence-ending characters.
                   1510: This is a Heirloom extension and currently ignored.
                   1511: .Ss \&shc
                   1512: Change the soft hyphen character.
                   1513: Currently ignored.
                   1514: .Ss \&shift
                   1515: Shift macro arguments.
                   1516: Currently unsupported.
                   1517: .Ss \&sizes
                   1518: Define permissible point sizes.
                   1519: This is a groff extension and currently ignored.
1.15      kristaps 1520: .Ss \&so
                   1521: Include a source file.
                   1522: Its syntax is as follows:
                   1523: .Pp
                   1524: .D1 Pf \. Cm \&so Ar file
                   1525: .Pp
                   1526: The
                   1527: .Ar file
                   1528: will be read and its contents processed as input in place of the
                   1529: .Sq \&.so
                   1530: request line.
1.28      kristaps 1531: To avoid inadvertent inclusion of unrelated files,
1.15      kristaps 1532: .Xr mandoc 1
                   1533: only accepts relative paths not containing the strings
                   1534: .Qq ../
                   1535: and
                   1536: .Qq /.. .
1.37      schwarze 1537: .Pp
                   1538: This request requires
                   1539: .Xr man 1
                   1540: to change to the right directory before calling
                   1541: .Xr mandoc 1 ,
                   1542: per convention to the root of the manual tree.
                   1543: Typical usage looks like:
                   1544: .Pp
                   1545: .Dl \&.so man3/Xcursor.3
                   1546: .Pp
                   1547: As the whole concept is rather fragile, the use of
                   1548: .Sx \&so
                   1549: is discouraged.
                   1550: Use
                   1551: .Xr ln 1
                   1552: instead.
1.63      schwarze 1553: .Ss \&spacewidth
                   1554: Set the space width from the font metrics file.
                   1555: This is a Heirloom extension and currently ignored.
                   1556: .Ss \&special
                   1557: Define a special font.
                   1558: This is a groff extension and currently ignored.
                   1559: .Ss \&spreadwarn
                   1560: Warn about wide spacing between words.
                   1561: Currently ignored.
                   1562: .Ss \&ss
                   1563: Set space character size.
                   1564: Currently ignored.
1.64      schwarze 1565: .Ss \&sty
1.63      schwarze 1566: Associate style with a font position.
                   1567: This is a groff extension and currently ignored.
                   1568: .Ss \&substring
                   1569: Replace a user-defined string with a substring.
                   1570: Currently unsupported.
                   1571: .Ss \&sv
                   1572: Save vertical space.
                   1573: Currently ignored.
                   1574: .Ss \&sy
                   1575: Execute shell command.
                   1576: Ignored because insecure.
                   1577: .Ss \&T&
                   1578: Re-start a table layout, retaining the options of the prior table
                   1579: invocation.
                   1580: See
                   1581: .Sx \&TS .
1.26      schwarze 1582: .Ss \&ta
                   1583: Set tab stops.
1.63      schwarze 1584: Takes an arbitrary number of arguments.
1.68      schwarze 1585: Currently unsupported.
1.63      schwarze 1586: .Ss \&tc
1.75      schwarze 1587: Change tab repetition character.
1.63      schwarze 1588: Currently unsupported.
                   1589: .Ss \&TE
                   1590: End a table context.
                   1591: See
                   1592: .Sx \&TS .
                   1593: .Ss \&ti
                   1594: Temporary indent.
1.68      schwarze 1595: Currently unsupported.
1.63      schwarze 1596: .Ss \&tkf
                   1597: Enable track kerning for a font.
                   1598: Currently ignored.
                   1599: .Ss \&tl
                   1600: Print a title line.
                   1601: Currently unsupported.
                   1602: .Ss \&tm
                   1603: Print to standard error output.
                   1604: Currently ignored.
                   1605: .Ss \&tm1
                   1606: Print to standard error output, allowing leading blanks.
                   1607: This is a groff extension and currently ignored.
                   1608: .Ss \&tmc
                   1609: Print to standard error output without a trailing newline.
                   1610: This is a groff extension and currently ignored.
1.6       schwarze 1611: .Ss \&tr
                   1612: Output character translation.
1.30      kristaps 1613: Its syntax is as follows:
                   1614: .Pp
                   1615: .D1 Pf \. Cm \&tr Ar [ab]+
                   1616: .Pp
                   1617: Pairs of
                   1618: .Ar ab
                   1619: characters are replaced
                   1620: .Ar ( a
                   1621: for
                   1622: .Ar b ) .
                   1623: Replacement (or origin) characters may also be character escapes; thus,
                   1624: .Pp
                   1625: .Dl tr \e(xx\e(yy
                   1626: .Pp
                   1627: replaces all invocations of \e(xx with \e(yy.
1.63      schwarze 1628: .Ss \&track
                   1629: Static letter space tracking.
                   1630: This is a Heirloom extension and currently ignored.
                   1631: .Ss \&transchar
                   1632: Define transparent characters for sentence-ending.
                   1633: This is a Heirloom extension and currently ignored.
                   1634: .Ss \&trf
                   1635: Output the contents of a file, disallowing invalid characters.
                   1636: This is a groff extension and ignored because insecure.
                   1637: .Ss \&trimat
                   1638: Set the TrimBox page parameter for PDF generation.
                   1639: This is a Heirloom extension and currently ignored.
                   1640: .Ss \&trin
                   1641: Output character translation, ignored by
                   1642: .Cm \&asciify .
                   1643: Currently unsupported.
                   1644: .Ss \&trnt
                   1645: Output character translation, ignored by \e!.
                   1646: Currently unsupported.
                   1647: .Ss \&troff
                   1648: Force troff mode.
                   1649: This is a groff extension and currently ignored.
1.20      kristaps 1650: .Ss \&TS
                   1651: Begin a table, which formats input in aligned rows and columns.
1.23      kristaps 1652: See
                   1653: .Xr tbl 7
                   1654: for a description of the tbl language.
1.63      schwarze 1655: .Ss \&uf
                   1656: Globally set the underline font.
                   1657: Currently ignored.
                   1658: .Ss \&ul
                   1659: Underline.
                   1660: Currently ignored.
                   1661: .Ss \&unformat
                   1662: Unformat spaces and tabs in a diversion.
                   1663: Currently unsupported.
                   1664: .Ss \&unwatch
                   1665: Disable notification for string or macro.
                   1666: This is a Heirloom extension and currently ignored.
                   1667: .Ss \&unwatchn
                   1668: Disable notification for register.
                   1669: This is a Heirloom extension and currently ignored.
                   1670: .Ss \&vpt
                   1671: Enable or disable vertical position traps.
                   1672: This is a groff extension and currently ignored.
                   1673: .Ss \&vs
                   1674: Change vertical spacing.
                   1675: Currently ignored.
                   1676: .Ss \&warn
                   1677: Set warning level.
                   1678: Currently ignored.
                   1679: .Ss \&warnscale
                   1680: Set the scaling indicator used in warnings.
                   1681: This is a groff extension and currently ignored.
                   1682: .Ss \&watch
                   1683: Notify on change of string or macro.
                   1684: This is a Heirloom extension and currently ignored.
                   1685: .Ss \&watchlength
                   1686: On change, report the contents of macros and strings
1.75      schwarze 1687: up to the specified length.
1.63      schwarze 1688: This is a Heirloom extension and currently ignored.
                   1689: .Ss \&watchn
                   1690: Notify on change of register.
                   1691: This is a Heirloom extension and currently ignored.
                   1692: .Ss \&wh
                   1693: Set a page location trap.
                   1694: Currently unsupported.
                   1695: .Ss \&while
                   1696: Repeated execution while a condition is true.
                   1697: Currently unsupported.
                   1698: .Ss \&write
                   1699: Write to an open file.
                   1700: Ignored because insecure.
                   1701: .Ss \&writec
                   1702: Write to an open file without appending a newline.
                   1703: Ignored because insecure.
                   1704: .Ss \&writem
                   1705: Write macro or string to an open file.
                   1706: Ignored because insecure.
                   1707: .Ss \&xflag
                   1708: Set the extension level.
                   1709: This is a Heirloom extension and currently ignored.
1.53      schwarze 1710: .Ss Numerical expressions
                   1711: The
                   1712: .Sx \&nr ,
                   1713: .Sx \&if ,
                   1714: and
                   1715: .Sx \&ie
                   1716: requests accept integer numerical expressions as arguments.
                   1717: These are always evaluated using the C
                   1718: .Vt int
                   1719: type; integer overflow works the same way as in the C language.
                   1720: Numbers consist of an arbitrary number of digits
                   1721: .Sq 0
                   1722: to
                   1723: .Sq 9
                   1724: prefixed by an optional sign
                   1725: .Sq +
                   1726: or
                   1727: .Sq - .
1.67      schwarze 1728: Each number may be followed by one optional scaling unit described below
                   1729: .Sx Scaling Widths .
                   1730: The following equations hold:
                   1731: .Bd -literal -offset indent
                   1732: 1i = 6v = 6P = 10m = 10n = 72p = 1000M = 240u = 240
1.68      schwarze 1733: 254c = 100i = 24000u = 24000
1.67      schwarze 1734: 1f = 65536u = 65536
                   1735: .Ed
1.53      schwarze 1736: .Pp
                   1737: The following binary operators are implemented.
                   1738: Unless otherwise stated, they behave as in the C language:
                   1739: .Pp
                   1740: .Bl -tag -width 2n -compact
                   1741: .It Ic +
                   1742: addition
                   1743: .It Ic -
                   1744: subtraction
                   1745: .It Ic *
                   1746: multiplication
                   1747: .It Ic /
                   1748: division
                   1749: .It Ic %
                   1750: remainder of division
                   1751: .It Ic <
                   1752: less than
                   1753: .It Ic >
                   1754: greater than
                   1755: .It Ic ==
                   1756: equal to
                   1757: .It Ic =
                   1758: equal to, same effect as
                   1759: .Ic ==
                   1760: (this differs from C)
                   1761: .It Ic <=
                   1762: less than or equal to
                   1763: .It Ic >=
                   1764: greater than or equal to
                   1765: .It Ic <>
                   1766: not equal to (corresponds to C
                   1767: .Ic != ;
                   1768: this one is of limited portability, it is supported by Heirloom roff,
                   1769: but not by groff)
                   1770: .It Ic &
                   1771: logical and (corresponds to C
                   1772: .Ic && )
                   1773: .It Ic \&:
                   1774: logical or (corresponds to C
                   1775: .Ic \&|| )
                   1776: .It Ic <?
                   1777: minimum (not available in C)
                   1778: .It Ic >?
                   1779: maximum (not available in C)
                   1780: .El
                   1781: .Pp
1.75      schwarze 1782: There is no concept of precedence; evaluation proceeds from left to right,
1.76    ! schwarze 1783: except when subexpressions are enclosed in parentheses.
1.53      schwarze 1784: Inside parentheses, whitespace is ignored.
1.46      schwarze 1785: .Sh ESCAPE SEQUENCE REFERENCE
                   1786: The
                   1787: .Xr mandoc 1
                   1788: .Nm
                   1789: parser recognises the following escape sequences.
                   1790: Note that the
                   1791: .Nm
                   1792: language defines more escape sequences not implemented in
                   1793: .Xr mandoc 1 .
                   1794: In
                   1795: .Xr mdoc 7
                   1796: and
                   1797: .Xr man 7
                   1798: documents, using escape sequences is discouraged except for those
                   1799: described in the
                   1800: .Sx LANGUAGE SYNTAX
                   1801: section above.
                   1802: .Pp
                   1803: A backslash followed by any character not listed here
                   1804: simply prints that character itself.
                   1805: .Ss \e<newline>
                   1806: A backslash at the end of an input line can be used to continue the
                   1807: logical input line on the next physical input line, joining the text
                   1808: on both lines together as if it were on a single input line.
                   1809: .Ss \e<space>
                   1810: The escape sequence backslash-space
                   1811: .Pq Sq \e\ \&
                   1812: is an unpaddable space-sized non-breaking space character; see
                   1813: .Sx Whitespace .
                   1814: .Ss \e\(dq
                   1815: The rest of the input line is treated as
                   1816: .Sx Comments .
                   1817: .Ss \e%
                   1818: Hyphenation allowed at this point of the word; ignored by
                   1819: .Xr mandoc 1 .
                   1820: .Ss \e&
                   1821: Non-printing zero-width character; see
                   1822: .Sx Whitespace .
                   1823: .Ss \e\(aq
                   1824: Acute accent special character; use
                   1825: .Sq \e(aa
                   1826: instead.
                   1827: .Ss \e( Ns Ar cc
                   1828: .Sx Special Characters
                   1829: with two-letter names, see
                   1830: .Xr mandoc_char 7 .
                   1831: .Ss \e*[ Ns Ar name ]
                   1832: Interpolate the string with the
                   1833: .Ar name ;
                   1834: see
                   1835: .Sx Predefined Strings
                   1836: and
                   1837: .Sx ds .
                   1838: For short names, there are variants
                   1839: .No \e* Ns Ar c
                   1840: and
                   1841: .No \e*( Ns Ar cc .
1.74      schwarze 1842: .Ss \e,
                   1843: Left italic correction (groff extension); ignored by
                   1844: .Xr mandoc 1 .
1.46      schwarze 1845: .Ss \e-
                   1846: Special character
                   1847: .Dq mathematical minus sign .
1.74      schwarze 1848: .Ss \e/
                   1849: Right italic correction (groff extension); ignored by
                   1850: .Xr mandoc 1 .
1.46      schwarze 1851: .Ss \e[ Ns Ar name ]
                   1852: .Sx Special Characters
                   1853: with names of arbitrary length, see
                   1854: .Xr mandoc_char 7 .
                   1855: .Ss \e^
                   1856: One-twelfth em half-narrow space character, effectively zero-width in
                   1857: .Xr mandoc 1 .
                   1858: .Ss \e`
                   1859: Grave accent special character; use
                   1860: .Sq \e(ga
                   1861: instead.
                   1862: .Ss \e{
                   1863: Begin conditional input; see
                   1864: .Sx if .
                   1865: .Ss \e\(ba
                   1866: One-sixth em narrow space character, effectively zero-width in
                   1867: .Xr mandoc 1 .
                   1868: .Ss \e}
                   1869: End conditional input; see
                   1870: .Sx if .
                   1871: .Ss \e~
                   1872: Paddable non-breaking space character.
                   1873: .Ss \e0
                   1874: Digit width space character.
                   1875: .Ss \eA\(aq Ns Ar string Ns \(aq
                   1876: Anchor definition; ignored by
                   1877: .Xr mandoc 1 .
                   1878: .Ss \eB\(aq Ns Ar string Ns \(aq
1.54      schwarze 1879: Interpolate
                   1880: .Sq 1
                   1881: if
1.46      schwarze 1882: .Ar string
1.54      schwarze 1883: conforms to the syntax of
                   1884: .Sx Numerical expressions
                   1885: explained above and
                   1886: .Sq 0
                   1887: otherwise.
1.46      schwarze 1888: .Ss \eb\(aq Ns Ar string Ns \(aq
                   1889: Bracket building function; ignored by
                   1890: .Xr mandoc 1 .
                   1891: .Ss \eC\(aq Ns Ar name Ns \(aq
                   1892: .Sx Special Characters
                   1893: with names of arbitrary length.
                   1894: .Ss \ec
1.60      schwarze 1895: When encountered at the end of an input text line,
                   1896: the next input text line is considered to continue that line,
                   1897: even if there are request or macro lines in between.
                   1898: No whitespace is inserted.
1.46      schwarze 1899: .Ss \eD\(aq Ns Ar string Ns \(aq
                   1900: Draw graphics function; ignored by
                   1901: .Xr mandoc 1 .
                   1902: .Ss \ed
                   1903: Move down by half a line; ignored by
                   1904: .Xr mandoc 1 .
                   1905: .Ss \ee
                   1906: Backslash special character.
                   1907: .Ss \eF[ Ns Ar name ]
                   1908: Switch font family (groff extension); ignored by
                   1909: .Xr mandoc 1 .
                   1910: For short names, there are variants
                   1911: .No \eF Ns Ar c
                   1912: and
                   1913: .No \eF( Ns Ar cc .
                   1914: .Ss \ef[ Ns Ar name ]
                   1915: Switch to the font
                   1916: .Ar name ,
                   1917: see
                   1918: .Sx Text Decoration .
                   1919: For short names, there are variants
                   1920: .No \ef Ns Ar c
                   1921: and
                   1922: .No \ef( Ns Ar cc .
                   1923: .Ss \eg[ Ns Ar name ]
                   1924: Interpolate the format of a number register; ignored by
                   1925: .Xr mandoc 1 .
                   1926: For short names, there are variants
                   1927: .No \eg Ns Ar c
                   1928: and
                   1929: .No \eg( Ns Ar cc .
                   1930: .Ss \eH\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
                   1931: Set the height of the current font; ignored by
                   1932: .Xr mandoc 1 .
                   1933: .Ss \eh\(aq Ns Ar number Ns \(aq
                   1934: Horizontal motion; ignored by
                   1935: .Xr mandoc 1 .
                   1936: .Ss \ek[ Ns Ar name ]
                   1937: Mark horizontal input place in register; ignored by
                   1938: .Xr mandoc 1 .
                   1939: For short names, there are variants
                   1940: .No \ek Ns Ar c
                   1941: and
                   1942: .No \ek( Ns Ar cc .
                   1943: .Ss \eL\(aq Ns Ar number Ns Oo Ar c Oc Ns \(aq
                   1944: Vertical line drawing function; ignored by
                   1945: .Xr mandoc 1 .
                   1946: .Ss \el\(aq Ns Ar number Ns Oo Ar c Oc Ns \(aq
                   1947: Horizontal line drawing function; ignored by
                   1948: .Xr mandoc 1 .
                   1949: .Ss \eM[ Ns Ar name ]
                   1950: Set fill (background) color (groff extension); ignored by
                   1951: .Xr mandoc 1 .
                   1952: For short names, there are variants
                   1953: .No \eM Ns Ar c
                   1954: and
                   1955: .No \eM( Ns Ar cc .
                   1956: .Ss \em[ Ns Ar name ]
                   1957: Set glyph drawing color (groff extension); ignored by
                   1958: .Xr mandoc 1 .
                   1959: For short names, there are variants
                   1960: .No \em Ns Ar c
                   1961: and
                   1962: .No \em( Ns Ar cc .
                   1963: .Ss \eN\(aq Ns Ar number Ns \(aq
                   1964: Character
                   1965: .Ar number
                   1966: on the current font.
                   1967: .Ss \en[ Ns Ar name ]
                   1968: Interpolate the number register
                   1969: .Ar name .
                   1970: For short names, there are variants
                   1971: .No \en Ns Ar c
                   1972: and
                   1973: .No \en( Ns Ar cc .
                   1974: .Ss \eo\(aq Ns Ar string Ns \(aq
1.66      schwarze 1975: Overstrike, writing all the characters contained in the
1.65      schwarze 1976: .Ar string
                   1977: to the same output position.
                   1978: In terminal and HTML output modes,
                   1979: only the last one of the characters is visible.
1.46      schwarze 1980: .Ss \eR\(aq Ns Ar name Oo +|- Oc Ns Ar number Ns \(aq
                   1981: Set number register; ignored by
                   1982: .Xr mandoc 1 .
                   1983: .Ss \eS\(aq Ns Ar number Ns \(aq
                   1984: Slant output; ignored by
                   1985: .Xr mandoc 1 .
                   1986: .Ss \es\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
                   1987: Change point size; ignored by
                   1988: .Xr mandoc 1 .
                   1989: Alternative forms
                   1990: .No \es Ns Oo +|- Oc Ns Ar n ,
                   1991: .No \es Ns Oo +|- Oc Ns \(aq Ns Ar number Ns \(aq ,
                   1992: .No \es Ns [ Oo +|- Oc Ns Ar number ] ,
                   1993: and
                   1994: .No \es Ns Oo +|- Oc Ns [ Ar number Ns ]
                   1995: are also parsed and ignored.
                   1996: .Ss \et
                   1997: Horizontal tab; ignored by
                   1998: .Xr mandoc 1 .
                   1999: .Ss \eu
                   2000: Move up by half a line; ignored by
                   2001: .Xr mandoc 1 .
                   2002: .Ss \eV[ Ns Ar name ]
                   2003: Interpolate an environment variable; ignored by
                   2004: .Xr mandoc 1 .
                   2005: For short names, there are variants
                   2006: .No \eV Ns Ar c
                   2007: and
                   2008: .No \eV( Ns Ar cc .
                   2009: .Ss \ev\(aq Ns Ar number Ns \(aq
                   2010: Vertical motion; ignored by
                   2011: .Xr mandoc 1 .
                   2012: .Ss \ew\(aq Ns Ar string Ns \(aq
                   2013: Interpolate the width of the
1.54      schwarze 2014: .Ar string .
                   2015: The
                   2016: .Xr mandoc 1
                   2017: implementation assumes that after expansion of user-defined strings, the
                   2018: .Ar string
                   2019: only contains normal characters, no escape sequences, and that each
                   2020: character has a width of 24 basic units.
1.46      schwarze 2021: .Ss \eX\(aq Ns Ar string Ns \(aq
                   2022: Output
                   2023: .Ar string
                   2024: as device control function; ignored in nroff mode and by
                   2025: .Xr mandoc 1 .
                   2026: .Ss \ex\(aq Ns Ar number Ns \(aq
                   2027: Extra line space function; ignored by
                   2028: .Xr mandoc 1 .
                   2029: .Ss \eY[ Ns Ar name ]
                   2030: Output a string as a device control function; ignored in nroff mode and by
                   2031: .Xr mandoc 1 .
                   2032: For short names, there are variants
                   2033: .No \eY Ns Ar c
                   2034: and
                   2035: .No \eY( Ns Ar cc .
                   2036: .Ss \eZ\(aq Ns Ar string Ns \(aq
                   2037: Print
                   2038: .Ar string
                   2039: with zero width and height; ignored by
                   2040: .Xr mandoc 1 .
                   2041: .Ss \ez
1.71      schwarze 2042: Output the next character without advancing the cursor position.
1.2       kristaps 2043: .Sh COMPATIBILITY
1.69      schwarze 2044: The
                   2045: .Xr mandoc 1
                   2046: implementation of the
1.17      schwarze 2047: .Nm
1.69      schwarze 2048: language is intentionally incomplete.
                   2049: Unimplemented features include:
1.2       kristaps 2050: .Pp
                   2051: .Bl -dash -compact
1.56      kristaps 2052: .It
1.69      schwarze 2053: For security reasons,
                   2054: .Xr mandoc 1
                   2055: never reads or writes external files except via
                   2056: .Sx \&so
                   2057: requests with safe relative paths.
                   2058: .It
                   2059: There is no automatic hyphenation, no adjustment to the right margin,
                   2060: and no centering; the output is always set flush-left.
                   2061: .It
                   2062: Support for setting tabulator positions
                   2063: and tabulator and leader characters is missing,
                   2064: and support for manually changing indentation is limited.
                   2065: .It
1.56      kristaps 2066: The
                   2067: .Sq u
                   2068: scaling unit is the default terminal unit.
1.69      schwarze 2069: In traditional troff systems, this unit changes depending on the
1.56      kristaps 2070: output media.
1.10      kristaps 2071: .It
1.69      schwarze 2072: Width measurements are implemented in a crude way
                   2073: and often yield wrong results.
                   2074: Explicit movement requests and escapes are ignored.
                   2075: .It
                   2076: There is no concept of output pages, no support for floats,
                   2077: graphics drawing, and picture inclusion;
                   2078: terminal output is always continuous.
                   2079: .It
                   2080: Requests regarding color, font families, and glyph manipulation
                   2081: are ignored.
                   2082: Font support is very limited.
                   2083: Kerning is not implemented, and no ligatures are produced.
1.27      kristaps 2084: .It
1.10      kristaps 2085: The
1.69      schwarze 2086: .Qq \(aq
                   2087: macro control character does not suppress output line breaks.
1.2       kristaps 2088: .It
1.69      schwarze 2089: Diversions are not implemented,
                   2090: and support for traps is very incomplete.
1.4       kristaps 2091: .It
1.69      schwarze 2092: While recursion is supported,
                   2093: .Sx \&while
                   2094: loops are not.
1.2       kristaps 2095: .El
1.69      schwarze 2096: .Pp
                   2097: The special semantics of the
                   2098: .Cm nS
                   2099: number register is an idiosyncracy of
                   2100: .Ox
                   2101: manuals and not supported by other
                   2102: .Xr mdoc 7
                   2103: implementations.
1.17      schwarze 2104: .Sh SEE ALSO
                   2105: .Xr mandoc 1 ,
1.27      kristaps 2106: .Xr eqn 7 ,
1.17      schwarze 2107: .Xr man 7 ,
                   2108: .Xr mandoc_char 7 ,
1.23      kristaps 2109: .Xr mdoc 7 ,
                   2110: .Xr tbl 7
1.17      schwarze 2111: .Rs
                   2112: .%A Joseph F. Ossanna
                   2113: .%A Brian W. Kernighan
                   2114: .%I AT&T Bell Laboratories
                   2115: .%T Troff User's Manual
                   2116: .%R Computing Science Technical Report
                   2117: .%N 54
                   2118: .%C Murray Hill, New Jersey
                   2119: .%D 1976 and 1992
                   2120: .%U http://www.kohala.com/start/troff/cstr54.ps
                   2121: .Re
                   2122: .Rs
                   2123: .%A Joseph F. Ossanna
                   2124: .%A Brian W. Kernighan
                   2125: .%A Gunnar Ritter
                   2126: .%T Heirloom Documentation Tools Nroff/Troff User's Manual
                   2127: .%D September 17, 2007
                   2128: .%U http://heirloom.sourceforge.net/doctools/troff.pdf
                   2129: .Re
                   2130: .Sh HISTORY
1.35      kristaps 2131: The RUNOFF typesetting system, whose input forms the basis for
1.17      schwarze 2132: .Nm ,
1.35      kristaps 2133: was written in MAD and FAP for the CTSS operating system by Jerome E.
                   2134: Saltzer in 1964.
                   2135: Doug McIlroy rewrote it in BCPL in 1969, renaming it
                   2136: .Nm .
                   2137: Dennis M. Ritchie rewrote McIlroy's
1.36      schwarze 2138: .Nm
                   2139: in PDP-11 assembly for
1.35      kristaps 2140: .At v1 ,
                   2141: Joseph F. Ossanna improved roff and renamed it nroff
                   2142: for
                   2143: .At v2 ,
                   2144: then ported nroff to C as troff, which Brian W. Kernighan released with
                   2145: .At v7 .
                   2146: In 1989, James Clarke re-implemented troff in C++, naming it groff.
1.1       kristaps 2147: .Sh AUTHORS
1.15      kristaps 2148: .An -nosplit
1.31      kristaps 2149: This
1.1       kristaps 2150: .Nm
                   2151: reference was written by
1.41      schwarze 2152: .An Kristaps Dzonsons Aq Mt kristaps@bsd.lv
1.15      kristaps 2153: and
1.41      schwarze 2154: .An Ingo Schwarze Aq Mt schwarze@openbsd.org .

CVSweb