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Annotation of mandoc/roff.7, Revision 1.93

1.93    ! schwarze    1: .\"    $Id: roff.7,v 1.92 2017/06/14 22:51:25 schwarze Exp $
1.1       kristaps    2: .\"
1.46      schwarze    3: .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
1.80      schwarze    4: .\" Copyright (c) 2010,2011,2013-2015,2017 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: .\"
1.89      schwarze   18: .Dd $Mdocdate: June 14 2017 $
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.
1.79      schwarze  400: .Bl -tag -width Ds
                    401: .It Ic \&ab Op Ar message
1.63      schwarze  402: Abort processing.
                    403: Currently unsupported.
1.79      schwarze  404: .It Ic \&ad Op Cm b | c | l | n | r
                    405: Set line adjustment mode for subsequent text.
1.63      schwarze  406: Currently ignored.
1.79      schwarze  407: .It Ic \&af Ar registername format
1.63      schwarze  408: Assign an output format to a number register.
                    409: Currently ignored.
1.79      schwarze  410: .It Ic \&aln Ar newname oldname
1.63      schwarze  411: Create an alias for a number register.
                    412: Currently unsupported.
1.79      schwarze  413: .It Ic \&als Ar newname oldname
1.63      schwarze  414: Create an alias for a request, string, macro, or diversion.
1.79      schwarze  415: .It Ic \&am Ar macroname Op Ar endmacro
1.15      kristaps  416: Append to a macro definition.
                    417: The syntax of this request is the same as that of
1.79      schwarze  418: .Ic \&de .
                    419: .It Ic \&am1 Ar macroname Op Ar endmacro
1.15      kristaps  420: Append to a macro definition, switching roff compatibility mode off
1.63      schwarze  421: during macro execution (groff extension).
1.15      kristaps  422: The syntax of this request is the same as that of
1.79      schwarze  423: .Ic \&de1 .
1.55      schwarze  424: Since
                    425: .Xr mandoc 1
                    426: does not implement
                    427: .Nm
                    428: compatibility mode at all, it handles this request as an alias for
1.79      schwarze  429: .Ic \&am .
                    430: .It Ic \&ami Ar macrostring Op Ar endstring
1.63      schwarze  431: Append to a macro definition, specifying the macro name indirectly
                    432: (groff extension).
                    433: The syntax of this request is the same as that of
1.79      schwarze  434: .Ic \&dei .
                    435: .It Ic \&ami1 Ar macrostring Op Ar endstring
1.63      schwarze  436: Append to a macro definition, specifying the macro name indirectly
                    437: and switching roff compatibility mode off during macro execution
                    438: (groff extension).
                    439: The syntax of this request is the same as that of
1.79      schwarze  440: .Ic \&dei1 .
1.63      schwarze  441: Since
                    442: .Xr mandoc 1
                    443: does not implement
                    444: .Nm
                    445: compatibility mode at all, it handles this request as an alias for
1.79      schwarze  446: .Ic \&ami .
                    447: .It Ic \&as Ar stringname Op Ar string
1.47      schwarze  448: Append to a user-defined string.
                    449: The syntax of this request is the same as that of
                    450: .Sx \&ds .
                    451: If a user-defined string with the specified name does not yet exist,
                    452: it is set to the empty string before appending.
1.79      schwarze  453: .It Ic \&as1 Ar stringname Op Ar string
1.63      schwarze  454: Append to a user-defined string, switching roff compatibility mode off
                    455: during macro execution (groff extension).
                    456: The syntax of this request is the same as that of
1.79      schwarze  457: .Ic \&ds1 .
1.63      schwarze  458: Since
                    459: .Xr mandoc 1
                    460: does not implement
                    461: .Nm
                    462: compatibility mode at all, it handles this request as an alias for
1.79      schwarze  463: .Ic \&as .
                    464: .It Ic \&asciify Ar divname
1.63      schwarze  465: Fully unformat a diversion.
                    466: Currently unsupported.
1.79      schwarze  467: .It Ic \&backtrace
1.63      schwarze  468: Print a backtrace of the input stack.
                    469: This is a groff extension and currently ignored.
1.79      schwarze  470: .It Ic \&bd Ar font Oo Ar curfont Oc Op Ar offset
1.63      schwarze  471: Artificially embolden by repeated printing with small shifts.
                    472: Currently ignored.
1.79      schwarze  473: .It Ic \&bleedat Ar left top width height
1.63      schwarze  474: Set the BleedBox page parameter for PDF generation.
                    475: This is a Heirloom extension and currently ignored.
1.79      schwarze  476: .It Ic \&blm Ar macroname
1.63      schwarze  477: Set a blank line trap.
                    478: Currently unsupported.
1.79      schwarze  479: .It Ic \&box Ar divname
1.63      schwarze  480: Begin a diversion without including a partially filled line.
                    481: Currently unsupported.
1.79      schwarze  482: .It Ic \&boxa Ar divname
1.63      schwarze  483: Add to a diversion without including a partially filled line.
                    484: Currently unsupported.
1.79      schwarze  485: .It Ic \&bp Oo Cm + Ns | Ns Cm - Oc Ns Ar pagenumber
                    486: Begin a new page.
1.63      schwarze  487: Currently ignored.
1.79      schwarze  488: .It Ic \&BP Ar source height width position offset flags label
1.63      schwarze  489: Define a frame and place a picture in it.
                    490: This is a Heirloom extension and currently unsupported.
1.79      schwarze  491: .It Ic \&br
1.63      schwarze  492: Break the output line.
1.79      schwarze  493: .It Ic \&break
1.63      schwarze  494: Break out of a
1.79      schwarze  495: .Ic \&while
1.63      schwarze  496: loop.
                    497: Currently unsupported.
1.79      schwarze  498: .It Ic \&breakchar Ar char ...
1.63      schwarze  499: Optional line break characters.
                    500: This is a Heirloom extension and currently ignored.
1.79      schwarze  501: .It Ic \&brnl Ar N
                    502: Break output line after the next
                    503: .Ar N
                    504: input lines.
1.63      schwarze  505: This is a Heirloom extension and currently ignored.
1.79      schwarze  506: .It Ic \&brp
1.63      schwarze  507: Break and spread output line.
                    508: Currently, this is implemented as an alias for
1.79      schwarze  509: .Ic \&br .
                    510: .It Ic \&brpnl Ar N
                    511: Break and spread output line after the next
                    512: .Ar N
                    513: input lines.
1.63      schwarze  514: This is a Heirloom extension and currently ignored.
1.79      schwarze  515: .It Ic \&c2 Op Ar char
1.63      schwarze  516: Change the no-break control character.
                    517: Currently unsupported.
1.79      schwarze  518: .It Ic \&cc Op Ar char
1.63      schwarze  519: Change the control character.
1.39      kristaps  520: If
1.79      schwarze  521: .Ar char
1.39      kristaps  522: is not specified, the control character is reset to
                    523: .Sq \&. .
                    524: Trailing characters are ignored.
1.79      schwarze  525: .It Ic \&ce Op Ar N
                    526: Center the next
                    527: .Ar N
                    528: input lines without filling.
1.85      schwarze  529: .Ar N
                    530: defaults to 1.
                    531: An argument of 0 or less ends centering.
1.86      schwarze  532: Currently, high level macros abort centering.
1.79      schwarze  533: .It Ic \&cf Ar filename
1.63      schwarze  534: Output the contents of a file.
                    535: Ignored because insecure.
1.79      schwarze  536: .It Ic \&cflags Ar flags char ...
1.63      schwarze  537: Set character flags.
                    538: This is a groff extension and currently ignored.
1.79      schwarze  539: .It Ic \&ch Ar macroname Op Ar dist
1.63      schwarze  540: Change a trap location.
                    541: Currently ignored.
1.79      schwarze  542: .It Ic \&char Ar glyphname Op Ar string
1.63      schwarze  543: Define a new glyph.
                    544: Currently unsupported.
1.79      schwarze  545: .It Ic \&chop Ar stringname
1.63      schwarze  546: Remove the last character from a macro, string, or diversion.
                    547: Currently unsupported.
1.79      schwarze  548: .It Ic \&class Ar classname char ...
1.63      schwarze  549: Define a character class.
                    550: This is a groff extension and currently ignored.
1.79      schwarze  551: .It Ic \&close Ar streamname
1.63      schwarze  552: Close an open file.
                    553: Ignored because insecure.
1.79      schwarze  554: .It Ic \&CL Ar color text
1.63      schwarze  555: Print text in color.
                    556: This is a Heirloom extension and currently unsupported.
1.79      schwarze  557: .It Ic \&color Op Cm 1 | 0
1.63      schwarze  558: Activate or deactivate colors.
                    559: This is a groff extension and currently ignored.
1.79      schwarze  560: .It Ic \&composite Ar from to
1.63      schwarze  561: Define a name component for composite glyph names.
                    562: This is a groff extension and currently unsupported.
1.79      schwarze  563: .It Ic \&continue
1.63      schwarze  564: Immediately start the next iteration of a
1.79      schwarze  565: .Ic \&while
1.63      schwarze  566: loop.
                    567: Currently unsupported.
1.79      schwarze  568: .It Ic \&cp Op Cm 1 | 0
1.63      schwarze  569: Switch
                    570: .Nm
                    571: compatibility mode on or off.
                    572: Currently ignored.
1.79      schwarze  573: .It Ic \&cropat Ar left top width height
1.63      schwarze  574: Set the CropBox page parameter for PDF generation.
                    575: This is a Heirloom extension and currently ignored.
1.79      schwarze  576: .It Ic \&cs Ar font Op Ar width Op Ar emsize
1.63      schwarze  577: Constant character spacing mode.
                    578: Currently ignored.
1.79      schwarze  579: .It Ic \&cu Op Ar N
                    580: Underline next
                    581: .Ar N
                    582: input lines including whitespace.
1.63      schwarze  583: Currently ignored.
1.79      schwarze  584: .It Ic \&da Ar divname
1.63      schwarze  585: Append to a diversion.
                    586: Currently unsupported.
1.79      schwarze  587: .It Ic \&dch Ar macroname Op Ar dist
1.63      schwarze  588: Change a trap location in the current diversion.
                    589: This is a Heirloom extension and currently unsupported.
1.79      schwarze  590: .It Ic \&de Ar macroname Op Ar endmacro
1.17      schwarze  591: Define a
1.15      kristaps  592: .Nm
                    593: macro.
                    594: Its syntax can be either
                    595: .Bd -literal -offset indent
1.79      schwarze  596: .Pf . Ic \&de Ar macroname
                    597: .Ar definition
1.15      kristaps  598: \&..
                    599: .Ed
                    600: .Pp
                    601: or
                    602: .Bd -literal -offset indent
1.79      schwarze  603: .Pf . Ic \&de Ar macroname Ar endmacro
                    604: .Ar definition
                    605: .Pf . Ar endmacro
1.15      kristaps  606: .Ed
                    607: .Pp
                    608: Both forms define or redefine the macro
1.79      schwarze  609: .Ar macroname
1.15      kristaps  610: to represent the
1.79      schwarze  611: .Ar definition ,
1.15      kristaps  612: which may consist of one or more input lines, including the newline
                    613: characters terminating each line, optionally containing calls to
                    614: .Nm
                    615: requests,
                    616: .Nm
                    617: macros or high-level macros like
                    618: .Xr man 7
                    619: or
                    620: .Xr mdoc 7
                    621: macros, whichever applies to the document in question.
                    622: .Pp
                    623: Specifying a custom
1.79      schwarze  624: .Ar endmacro
1.15      kristaps  625: macro works in the same way as for
1.79      schwarze  626: .Ic \&ig ;
1.15      kristaps  627: namely, the call to
1.79      schwarze  628: .Sq Pf . Ar endmacro
1.15      kristaps  629: first ends the
1.79      schwarze  630: .Ar definition ,
1.15      kristaps  631: and after that, it is also evaluated as a
                    632: .Nm
                    633: request or
                    634: .Nm
                    635: macro, but not as a high-level macro.
                    636: .Pp
1.17      schwarze  637: The macro can be invoked later using the syntax
1.15      kristaps  638: .Pp
1.79      schwarze  639: .D1 Pf . Ar macroname Op Ar argument Op Ar argument ...
1.15      kristaps  640: .Pp
1.24      schwarze  641: Regarding argument parsing, see
                    642: .Sx MACRO SYNTAX
                    643: above.
1.15      kristaps  644: .Pp
1.17      schwarze  645: The line invoking the macro will be replaced
1.15      kristaps  646: in the input stream by the
1.79      schwarze  647: .Ar definition ,
1.15      kristaps  648: replacing all occurrences of
                    649: .No \e\e$ Ns Ar N ,
1.17      schwarze  650: where
1.15      kristaps  651: .Ar N
                    652: is a digit, by the
                    653: .Ar N Ns th Ar argument .
                    654: For example,
                    655: .Bd -literal -offset indent
                    656: \&.de ZN
                    657: \efI\e^\e\e$1\e^\efP\e\e$2
                    658: \&..
                    659: \&.ZN XtFree .
                    660: .Ed
                    661: .Pp
                    662: produces
                    663: .Pp
                    664: .D1 \efI\e^XtFree\e^\efP.
                    665: .Pp
                    666: in the input stream, and thus in the output: \fI\^XtFree\^\fP.
1.73      schwarze  667: Each occurrence of \e\e$* is replaced with all the arguments,
                    668: joined together with single blank characters.
1.15      kristaps  669: .Pp
1.17      schwarze  670: Since macros and user-defined strings share a common string table,
1.15      kristaps  671: defining a macro
1.79      schwarze  672: .Ar macroname
1.15      kristaps  673: clobbers the user-defined string
1.79      schwarze  674: .Ar macroname ,
1.15      kristaps  675: and the
1.79      schwarze  676: .Ar definition
1.15      kristaps  677: can also be printed using the
                    678: .Sq \e*
                    679: string interpolation syntax described below
1.79      schwarze  680: .Ic ds ,
1.15      kristaps  681: but this is rarely useful because every macro definition contains at least
                    682: one explicit newline character.
1.16      schwarze  683: .Pp
                    684: In order to prevent endless recursion, both groff and
                    685: .Xr mandoc 1
                    686: limit the stack depth for expanding macros and strings
1.61      schwarze  687: to a large, but finite number, and
                    688: .Xr mandoc 1
                    689: also limits the length of the expanded input line.
                    690: Do not rely on the exact values of these limits.
1.79      schwarze  691: .It Ic \&de1 Ar macroname Op Ar endmacro
1.63      schwarze  692: Define a
                    693: .Nm
                    694: macro that will be executed with
                    695: .Nm
                    696: compatibility mode switched off during macro execution.
                    697: This is a groff extension.
                    698: Since
                    699: .Xr mandoc 1
                    700: does not implement
                    701: .Nm
                    702: compatibility mode at all, it handles this request as an alias for
1.79      schwarze  703: .Ic \&de .
                    704: .It Ic \&defcolor Ar newname scheme component ...
1.63      schwarze  705: Define a color name.
                    706: This is a groff extension and currently ignored.
1.79      schwarze  707: .It Ic \&dei Ar macrostring Op Ar endstring
1.17      schwarze  708: Define a
1.15      kristaps  709: .Nm
1.63      schwarze  710: macro, specifying the macro name indirectly (groff extension).
1.17      schwarze  711: The syntax of this request is the same as that of
1.79      schwarze  712: .Ic \&de .
                    713: The effect is the same as:
1.55      schwarze  714: .Pp
1.79      schwarze  715: .D1 Pf . Cm \&de No \e* Ns Bo Ar macrostring Bc Op \e* Ns Bq Ar endstring
                    716: .It Ic \&dei1 Ar macrostring Op Ar endstring
1.17      schwarze  717: Define a
1.15      kristaps  718: .Nm
                    719: macro that will be executed with
                    720: .Nm
1.63      schwarze  721: compatibility mode switched off during macro execution,
                    722: specifying the macro name indirectly (groff extension).
1.15      kristaps  723: Since
                    724: .Xr mandoc 1
                    725: does not implement
                    726: .Nm
1.17      schwarze  727: compatibility mode at all, it handles this request as an alias for
1.79      schwarze  728: .Ic \&dei .
                    729: .It Ic \&device Ar string ...
                    730: .It Ic \&devicem Ar stringname
                    731: These two requests only make sense with the groff-specific intermediate
                    732: output format and are unsupported.
                    733: .It Ic \&di Ar divname
1.63      schwarze  734: Begin a diversion.
                    735: Currently unsupported.
1.79      schwarze  736: .It Ic \&do Ar command Op Ar argument ...
1.63      schwarze  737: Execute
                    738: .Nm
                    739: request or macro line with compatibility mode disabled.
                    740: Currently unsupported.
1.79      schwarze  741: .It Ic \&ds Ar stringname Op Oo \(dq Oc Ns Ar string
1.15      kristaps  742: Define a user-defined string.
1.13      kristaps  743: The
1.79      schwarze  744: .Ar stringname
1.13      kristaps  745: and
1.15      kristaps  746: .Ar string
                    747: arguments are space-separated.
                    748: If the
                    749: .Ar string
                    750: begins with a double-quote character, that character will not be part
                    751: of the string.
                    752: All remaining characters on the input line form the
                    753: .Ar string ,
                    754: including whitespace and double-quote characters, even trailing ones.
                    755: .Pp
1.13      kristaps  756: The
1.15      kristaps  757: .Ar string
                    758: can be interpolated into subsequent text by using
1.79      schwarze  759: .No \e* Ns Bq Ar stringname
1.15      kristaps  760: for a
1.79      schwarze  761: .Ar stringname
1.15      kristaps  762: of arbitrary length, or \e*(NN or \e*N if the length of
1.79      schwarze  763: .Ar stringname
1.15      kristaps  764: is two or one characters, respectively.
1.17      schwarze  765: Interpolation can be prevented by escaping the leading backslash;
                    766: that is, an asterisk preceded by an even number of backslashes
                    767: does not trigger string interpolation.
1.15      kristaps  768: .Pp
                    769: Since user-defined strings and macros share a common string table,
                    770: defining a string
1.79      schwarze  771: .Ar stringname
1.17      schwarze  772: clobbers the macro
1.79      schwarze  773: .Ar stringname ,
1.15      kristaps  774: and the
1.79      schwarze  775: .Ar stringname
1.15      kristaps  776: used for defining a string can also be invoked as a macro,
                    777: in which case the following input line will be appended to the
                    778: .Ar string ,
                    779: forming a new input line passed to the
                    780: .Nm
                    781: parser.
                    782: For example,
                    783: .Bd -literal -offset indent
                    784: \&.ds badidea .S
                    785: \&.badidea
                    786: H SYNOPSIS
                    787: .Ed
                    788: .Pp
                    789: invokes the
1.79      schwarze  790: .Ic SH
1.15      kristaps  791: macro when used in a
                    792: .Xr man 7
                    793: document.
                    794: Such abuse is of course strongly discouraged.
1.79      schwarze  795: .It Ic \&ds1 Ar stringname Op Oo \(dq Oc Ns Ar string
1.63      schwarze  796: Define a user-defined string that will be expanded with
                    797: .Nm
                    798: compatibility mode switched off during string expansion.
                    799: This is a groff extension.
                    800: Since
                    801: .Xr mandoc 1
                    802: does not implement
                    803: .Nm
                    804: compatibility mode at all, it handles this request as an alias for
1.79      schwarze  805: .Ic \&ds .
                    806: .It Ic \&dwh Ar dist macroname
1.63      schwarze  807: Set a location trap in the current diversion.
                    808: This is a Heirloom extension and currently unsupported.
1.79      schwarze  809: .It Ic \&dt Op Ar dist macroname
1.63      schwarze  810: Set a trap within a diversion.
                    811: Currently unsupported.
1.79      schwarze  812: .It Ic \&ec Op Ar char
1.83      schwarze  813: Enable the escape mechanism and change the escape character.
                    814: The
                    815: .Ar char
                    816: argument defaults to the backslash
                    817: .Pq Sq \e .
1.79      schwarze  818: .It Ic \&ecr
1.63      schwarze  819: Restore the escape character.
                    820: Currently unsupported.
1.79      schwarze  821: .It Ic \&ecs
1.63      schwarze  822: Save the escape character.
                    823: Currently unsupported.
1.79      schwarze  824: .It Ic \&el Ar body
1.5       kristaps  825: The
1.79      schwarze  826: .Dq else
1.5       kristaps  827: half of an if/else conditional.
                    828: Pops a result off the stack of conditional evaluations pushed by
1.79      schwarze  829: .Ic \&ie
1.5       kristaps  830: and uses it as its conditional.
                    831: If no stack entries are present (e.g., due to no prior
1.79      schwarze  832: .Ic \&ie
1.5       kristaps  833: calls)
                    834: then false is assumed.
1.17      schwarze  835: The syntax of this request is similar to
1.79      schwarze  836: .Ic \&if
1.5       kristaps  837: except that the conditional is missing.
1.79      schwarze  838: .It Ic \&em Ar macroname
1.63      schwarze  839: Set a trap at the end of input.
                    840: Currently unsupported.
1.79      schwarze  841: .It Ic \&EN
1.27      kristaps  842: End an equation block.
                    843: See
1.79      schwarze  844: .Ic \&EQ .
                    845: .It Ic \&eo
1.63      schwarze  846: Disable the escape mechanism completely.
1.79      schwarze  847: .It Ic \&EP
1.63      schwarze  848: End a picture started by
1.79      schwarze  849: .Ic \&BP .
1.63      schwarze  850: This is a Heirloom extension and currently unsupported.
1.79      schwarze  851: .It Ic \&EQ
1.27      kristaps  852: Begin an equation block.
                    853: See
                    854: .Xr eqn 7
                    855: for a description of the equation language.
1.79      schwarze  856: .It Ic \&errprint Ar message
1.63      schwarze  857: Print a string like an error message.
                    858: This is a Heirloom extension and currently ignored.
1.79      schwarze  859: .It Ic \&ev Op Ar envname
1.63      schwarze  860: Switch to another environment.
                    861: Currently unsupported.
1.79      schwarze  862: .It Ic \&evc Op Ar envname
1.63      schwarze  863: Copy an environment into the current environment.
                    864: Currently unsupported.
1.79      schwarze  865: .It Ic \&ex
1.63      schwarze  866: Abort processing and exit.
                    867: Currently unsupported.
1.79      schwarze  868: .It Ic \&fallback Ar curfont font ...
1.63      schwarze  869: Select the fallback sequence for a font.
                    870: This is a Heirloom extension and currently ignored.
1.79      schwarze  871: .It Ic \&fam Op Ar familyname
1.43      schwarze  872: Change the font family.
1.79      schwarze  873: This is a groff extension and currently ignored.
                    874: .It Ic \&fc Op Ar delimchar Op Ar padchar
1.63      schwarze  875: Define a delimiting and a padding character for fields.
                    876: Currently unsupported.
1.79      schwarze  877: .It Ic \&fchar Ar glyphname Op Ar string
1.63      schwarze  878: Define a fallback glyph.
                    879: Currently unsupported.
1.79      schwarze  880: .It Ic \&fcolor Ar colorname
1.63      schwarze  881: Set the fill color for \eD objects.
                    882: This is a groff extension and currently ignored.
1.79      schwarze  883: .It Ic \&fdeferlig Ar font string ...
1.63      schwarze  884: Defer ligature building.
                    885: This is a Heirloom extension and currently ignored.
1.79      schwarze  886: .It Ic \&feature Cm + Ns | Ns Cm - Ns Ar name
1.63      schwarze  887: Enable or disable an OpenType feature.
                    888: This is a Heirloom extension and currently ignored.
1.79      schwarze  889: .It Ic \&fi
1.63      schwarze  890: Switch to fill mode.
                    891: See
                    892: .Xr man 7 .
                    893: Ignored in
                    894: .Xr mdoc 7 .
1.79      schwarze  895: .It Ic \&fkern Ar font minkern
1.63      schwarze  896: Control the use of kerning tables for a font.
                    897: This is a Heirloom extension and currently ignored.
1.79      schwarze  898: .It Ic \&fl
1.63      schwarze  899: Flush output.
                    900: Currently ignored.
1.79      schwarze  901: .It Ic \&flig Ar font string char ...
1.63      schwarze  902: Define ligatures.
                    903: This is a Heirloom extension and currently ignored.
1.79      schwarze  904: .It Ic \&fp Ar position font Op Ar filename
1.63      schwarze  905: Assign font position.
                    906: Currently ignored.
1.79      schwarze  907: .It Ic \&fps Ar mapname ...
1.63      schwarze  908: Mount a font with a special character map.
                    909: This is a Heirloom extension and currently ignored.
1.79      schwarze  910: .It Ic \&fschar Ar font glyphname Op Ar string
1.63      schwarze  911: Define a font-specific fallback glyph.
                    912: This is a groff extension and currently unsupported.
1.79      schwarze  913: .It Ic \&fspacewidth Ar font Op Ar afmunits
1.63      schwarze  914: Set a font-specific width for the space character.
                    915: This is a Heirloom extension and currently ignored.
1.79      schwarze  916: .It Ic \&fspecial Ar curfont Op Ar font ...
1.63      schwarze  917: Conditionally define a special font.
                    918: This is a groff extension and currently ignored.
1.79      schwarze  919: .It Ic \&ft Op Ar font
1.49      schwarze  920: Change the font.
                    921: The following
                    922: .Ar font
                    923: arguments are supported:
                    924: .Bl -tag -width 4n -offset indent
                    925: .It Cm B , BI , 3 , 4
                    926: switches to
                    927: .Sy bold
                    928: font
                    929: .It Cm I , 2
                    930: switches to
                    931: .Em underlined
                    932: font
                    933: .It Cm R , CW , 1
                    934: switches to normal font
                    935: .It Cm P No "or no argument"
                    936: switches back to the previous font
                    937: .El
                    938: .Pp
1.77      schwarze  939: This request takes effect only locally and may be overridden
                    940: by macros and escape sequences.
1.79      schwarze  941: .It Ic \&ftr Ar newname Op Ar oldname
1.63      schwarze  942: Translate font name.
                    943: This is a groff extension and currently ignored.
1.79      schwarze  944: .It Ic \&fzoom Ar font Op Ar permille
1.63      schwarze  945: Zoom font size.
                    946: Currently ignored.
1.79      schwarze  947: .It Ic \&gcolor Op Ar colorname
1.63      schwarze  948: Set glyph color.
                    949: This is a groff extension and currently ignored.
1.79      schwarze  950: .It Ic \&hc Op Ar char
1.63      schwarze  951: Set the hyphenation character.
                    952: Currently ignored.
1.79      schwarze  953: .It Ic \&hcode Ar char code ...
1.63      schwarze  954: Set hyphenation codes of characters.
                    955: Currently ignored.
1.79      schwarze  956: .It Ic \&hidechar Ar font char ...
1.63      schwarze  957: Hide characters in a font.
                    958: This is a Heirloom extension and currently ignored.
1.79      schwarze  959: .It Ic \&hla Ar language
1.63      schwarze  960: Set hyphenation language.
                    961: This is a groff extension and currently ignored.
1.79      schwarze  962: .It Ic \&hlm Op Ar number
1.63      schwarze  963: Set maximum number of consecutive hyphenated lines.
                    964: Currently ignored.
1.79      schwarze  965: .It Ic \&hpf Ar filename
1.63      schwarze  966: Load hyphenation pattern file.
                    967: This is a groff extension and currently ignored.
1.79      schwarze  968: .It Ic \&hpfa Ar filename
1.63      schwarze  969: Load hyphenation pattern file, appending to the current patterns.
                    970: This is a groff extension and currently ignored.
1.79      schwarze  971: .It Ic \&hpfcode Ar code code ...
1.63      schwarze  972: Define mapping values for character codes in hyphenation patterns.
                    973: This is a groff extension and currently ignored.
1.79      schwarze  974: .It Ic \&hw Ar word ...
1.44      schwarze  975: Specify hyphenation points in words.
1.63      schwarze  976: Currently ignored.
1.79      schwarze  977: .It Ic \&hy Op Ar mode
1.15      kristaps  978: Set automatic hyphenation mode.
1.63      schwarze  979: Currently ignored.
1.79      schwarze  980: .It Ic \&hylang Ar language
1.63      schwarze  981: Set hyphenation language.
                    982: This is a Heirloom extension and currently ignored.
1.79      schwarze  983: .It Ic \&hylen Ar nchar
1.63      schwarze  984: Minimum word length for hyphenation.
                    985: This is a Heirloom extension and currently ignored.
1.79      schwarze  986: .It Ic \&hym Op Ar length
1.63      schwarze  987: Set hyphenation margin.
                    988: This is a groff extension and currently ignored.
1.79      schwarze  989: .It Ic \&hypp Ar penalty ...
1.63      schwarze  990: Define hyphenation penalties.
                    991: This is a Heirloom extension and currently ignored.
1.79      schwarze  992: .It Ic \&hys Op Ar length
1.63      schwarze  993: Set hyphenation space.
                    994: This is a groff extension and currently ignored.
1.79      schwarze  995: .It Ic \&ie Ar condition body
1.5       kristaps  996: The
1.79      schwarze  997: .Dq if
1.5       kristaps  998: half of an if/else conditional.
                    999: The result of the conditional is pushed into a stack used by subsequent
                   1000: invocations of
1.79      schwarze 1001: .Ic \&el ,
1.5       kristaps 1002: which may be separated by any intervening input (or not exist at all).
                   1003: Its syntax is equivalent to
1.79      schwarze 1004: .Ic \&if .
                   1005: .It Ic \&if Ar condition body
                   1006: Begin a conditional.
                   1007: This request can also be written as follows:
                   1008: .Bd -unfilled -offset indent
                   1009: .Pf . Ic \&if Ar condition No \e{ Ns Ar body
                   1010: .Ar body ... Ns \e}
1.48      schwarze 1011: .Ed
1.79      schwarze 1012: .Bd -unfilled -offset indent
                   1013: .Pf . Ic \&if Ar condition No \e{\e
                   1014: .Ar body ...
                   1015: .Pf . No \e}
1.48      schwarze 1016: .Ed
                   1017: .Pp
1.79      schwarze 1018: The
                   1019: .Ar condition
                   1020: is a boolean expression.
1.48      schwarze 1021: Currently,
                   1022: .Xr mandoc 1
                   1023: supports the following subset of roff conditionals:
                   1024: .Bl -bullet
                   1025: .It
                   1026: If
                   1027: .Sq \&!
1.79      schwarze 1028: is prefixed to
                   1029: .Ar condition ,
                   1030: it is logically inverted.
1.48      schwarze 1031: .It
1.79      schwarze 1032: If the first character of
                   1033: .Ar condition
                   1034: is
1.48      schwarze 1035: .Sq n
                   1036: .Pq nroff mode
                   1037: or
                   1038: .Sq o
                   1039: .Pq odd page ,
1.79      schwarze 1040: it evaluates to true.
1.48      schwarze 1041: .It
1.79      schwarze 1042: If the first character of
                   1043: .Ar condition
                   1044: is
1.48      schwarze 1045: .Sq c
                   1046: .Pq character available ,
                   1047: .Sq e
                   1048: .Pq even page ,
                   1049: .Sq t
                   1050: .Pq troff mode ,
1.59      schwarze 1051: or
                   1052: .Sq v
                   1053: .Pq vroff mode ,
1.79      schwarze 1054: it evaluates to false.
1.90      schwarze 1055: .It
                   1056: If the first character of
                   1057: .Ar condition
                   1058: is
                   1059: .Sq d ,
                   1060: it evaluates to true if the rest of
                   1061: .Ar condition
                   1062: is the name of an existing user defined macro or string;
                   1063: otherwise, it evaluates to false.
1.72      schwarze 1064: .It
1.79      schwarze 1065: If the first character of
                   1066: .Ar condition
                   1067: is
1.72      schwarze 1068: .Sq r ,
1.79      schwarze 1069: it evaluates to true if the rest of
                   1070: .Ar condition
                   1071: is the name of an existing number register;
                   1072: otherwise, it evaluates to false.
1.48      schwarze 1073: .It
1.79      schwarze 1074: If the
                   1075: .Ar condition
                   1076: starts with a parenthesis or with an optionally signed
1.53      schwarze 1077: integer number, it is evaluated according to the rules of
                   1078: .Sx Numerical expressions
                   1079: explained below.
1.57      schwarze 1080: It evaluates to true if the result is positive,
1.53      schwarze 1081: or to false if the result is zero or negative.
1.48      schwarze 1082: .It
1.79      schwarze 1083: Otherwise, the first character of
                   1084: .Ar condition
                   1085: is regarded as a delimiter and it evaluates to true if the string
                   1086: extending from its first to its second occurrence is equal to the
                   1087: string extending from its second to its third occurrence.
1.48      schwarze 1088: .It
1.79      schwarze 1089: If
                   1090: .Ar condition
                   1091: cannot be parsed, it evaluates to false.
1.48      schwarze 1092: .El
                   1093: .Pp
1.3       kristaps 1094: If a conditional is false, its children are not processed, but are
                   1095: syntactically interpreted to preserve the integrity of the input
                   1096: document.
                   1097: Thus,
                   1098: .Pp
1.17      schwarze 1099: .D1 \&.if t .ig
1.3       kristaps 1100: .Pp
                   1101: will discard the
                   1102: .Sq \&.ig ,
                   1103: which may lead to interesting results, but
                   1104: .Pp
1.17      schwarze 1105: .D1 \&.if t .if t \e{\e
1.3       kristaps 1106: .Pp
                   1107: will continue to syntactically interpret to the block close of the final
                   1108: conditional.
                   1109: Sub-conditionals, in this case, obviously inherit the truth value of
                   1110: the parent.
1.1       kristaps 1111: .Pp
1.79      schwarze 1112: If the
                   1113: .Ar body
                   1114: section is begun by an escaped brace
1.1       kristaps 1115: .Sq \e{ ,
1.48      schwarze 1116: scope continues until the end of the input line containing the
                   1117: matching closing-brace escape sequence
                   1118: .Sq \e} .
1.79      schwarze 1119: If the
                   1120: .Ar body
                   1121: is not enclosed in braces, scope continues until the end of the line.
                   1122: If the
                   1123: .Ar condition
                   1124: is followed by a
                   1125: .Ar body
                   1126: on the same line, whether after a brace or not, then requests and macros
1.1       kristaps 1127: .Em must
                   1128: begin with a control character.
                   1129: It is generally more intuitive, in this case, to write
1.79      schwarze 1130: .Bd -unfilled -offset indent
                   1131: .Pf . Ic \&if Ar condition No \e{\e
                   1132: .Pf . Ar request
                   1133: .Pf . No \e}
1.1       kristaps 1134: .Ed
                   1135: .Pp
1.17      schwarze 1136: than having the request or macro follow as
1.1       kristaps 1137: .Pp
1.79      schwarze 1138: .D1 Pf . Ic \&if Ar condition Pf \e{. Ar request
1.1       kristaps 1139: .Pp
                   1140: The scope of a conditional is always parsed, but only executed if the
                   1141: conditional evaluates to true.
                   1142: .Pp
1.29      kristaps 1143: Note that the
1.1       kristaps 1144: .Sq \e}
1.29      kristaps 1145: is converted into a zero-width escape sequence if not passed as a
                   1146: standalone macro
                   1147: .Sq \&.\e} .
                   1148: For example,
                   1149: .Pp
                   1150: .D1 \&.Fl a \e} b
                   1151: .Pp
                   1152: will result in
1.8       kristaps 1153: .Sq \e}
1.29      kristaps 1154: being considered an argument of the
                   1155: .Sq \&Fl
                   1156: macro.
1.79      schwarze 1157: .It Ic \&ig Op Ar endmacro
1.2       kristaps 1158: Ignore input.
1.15      kristaps 1159: Its syntax can be either
                   1160: .Bd -literal -offset indent
                   1161: .Pf . Cm \&ig
                   1162: .Ar ignored text
1.2       kristaps 1163: \&..
                   1164: .Ed
1.15      kristaps 1165: .Pp
                   1166: or
                   1167: .Bd -literal -offset indent
1.79      schwarze 1168: .Pf . Cm \&ig Ar endmacro
1.15      kristaps 1169: .Ar ignored text
1.79      schwarze 1170: .Pf . Ar endmacro
1.2       kristaps 1171: .Ed
                   1172: .Pp
                   1173: In the first case, input is ignored until a
                   1174: .Sq \&..
1.17      schwarze 1175: request is encountered on its own line.
1.15      kristaps 1176: In the second case, input is ignored until the specified
1.79      schwarze 1177: .Sq Pf . Ar endmacro
                   1178: is encountered.
1.15      kristaps 1179: Do not use the escape character
1.2       kristaps 1180: .Sq \e
1.15      kristaps 1181: anywhere in the definition of
1.79      schwarze 1182: .Ar endmacro ;
1.15      kristaps 1183: it would cause very strange behaviour.
                   1184: .Pp
                   1185: When the
1.79      schwarze 1186: .Ar endmacro
                   1187: is a roff request or a roff macro, like in
1.2       kristaps 1188: .Pp
                   1189: .D1 \&.ig if
                   1190: .Pp
                   1191: the subsequent invocation of
1.79      schwarze 1192: .Ic \&if
1.15      kristaps 1193: will first terminate the
                   1194: .Ar ignored text ,
                   1195: then be invoked as usual.
                   1196: Otherwise, it only terminates the
                   1197: .Ar ignored text ,
                   1198: and arguments following it or the
                   1199: .Sq \&..
1.17      schwarze 1200: request are discarded.
1.79      schwarze 1201: .It Ic \&in Op Oo Cm + Ns | Ns Cm - Oc Ns Ar width
1.63      schwarze 1202: Change indentation.
                   1203: See
                   1204: .Xr man 7 .
                   1205: Ignored in
                   1206: .Xr mdoc 7 .
1.79      schwarze 1207: .It Ic \&index Ar register stringname substring
1.63      schwarze 1208: Find a substring in a string.
                   1209: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1210: .It Ic \&it Ar expression macro
1.63      schwarze 1211: Set an input line trap.
                   1212: The named
                   1213: .Ar macro
1.70      schwarze 1214: will be invoked after processing the number of input text lines
                   1215: specified by the numerical
                   1216: .Ar expression .
                   1217: While evaluating the
                   1218: .Ar expression ,
                   1219: the unit suffixes described below
                   1220: .Sx Scaling Widths
                   1221: are ignored.
1.79      schwarze 1222: .It Ic \&it Ar expression macro
1.63      schwarze 1223: Set an input line trap, not counting lines ending with \ec.
                   1224: Currently unsupported.
1.79      schwarze 1225: .It Ic \&IX Ar class keystring
1.63      schwarze 1226: To support the generation of a table of contents,
                   1227: .Xr pod2man 1
                   1228: emits this user-defined macro, usually without defining it.
                   1229: To avoid reporting large numbers of spurious errors,
                   1230: .Xr mandoc 1
                   1231: ignores it.
1.79      schwarze 1232: .It Ic \&kern Op Cm 1 | 0
1.63      schwarze 1233: Switch kerning on or off.
                   1234: Currently ignored.
1.79      schwarze 1235: .It Ic \&kernafter Ar font char ... afmunits ...
1.63      schwarze 1236: Increase kerning after some characters.
                   1237: This is a Heirloom extension and currently ignored.
1.79      schwarze 1238: .It Ic \&kernbefore Ar font char ... afmunits ...
1.63      schwarze 1239: Increase kerning before some characters.
                   1240: This is a Heirloom extension and currently ignored.
1.79      schwarze 1241: .It Ic \&kernpair Ar font char ... font char ... afmunits
1.63      schwarze 1242: Add a kerning pair to the kerning table.
                   1243: This is a Heirloom extension and currently ignored.
1.79      schwarze 1244: .It Ic \&lc Op Ar glyph
1.63      schwarze 1245: Define a leader repetition character.
                   1246: Currently unsupported.
1.79      schwarze 1247: .It Ic \&lc_ctype Ar localename
1.63      schwarze 1248: Set the
                   1249: .Dv LC_CTYPE
                   1250: locale.
                   1251: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1252: .It Ic \&lds Ar macroname string
1.63      schwarze 1253: Define a local string.
                   1254: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1255: .It Ic \&length Ar register string
                   1256: Count the number of input characters in a string.
1.63      schwarze 1257: Currently unsupported.
1.79      schwarze 1258: .It Ic \&letadj Ar lspmin lshmin letss lspmax lshmax
1.63      schwarze 1259: Dynamic letter spacing and reshaping.
                   1260: This is a Heirloom extension and currently ignored.
1.79      schwarze 1261: .It Ic \&lf Ar lineno Op Ar filename
1.63      schwarze 1262: Change the line number for error messages.
                   1263: Ignored because insecure.
1.79      schwarze 1264: .It Ic \&lg Op Cm 1 | 0
1.63      schwarze 1265: Switch the ligature mechanism on or off.
                   1266: Currently ignored.
1.79      schwarze 1267: .It Ic \&lhang Ar font char ... afmunits
1.63      schwarze 1268: Hang characters at left margin.
                   1269: This is a Heirloom extension and currently ignored.
1.79      schwarze 1270: .It Ic \&linetabs Op Cm 1 | 0
1.63      schwarze 1271: Enable or disable line-tabs mode.
                   1272: This is a groff extension and currently unsupported.
1.79      schwarze 1273: .It Ic \&ll Op Oo Cm + Ns | Ns Cm - Oc Ns Ar width
1.50      schwarze 1274: Change the output line length.
                   1275: If the
                   1276: .Ar width
                   1277: argument is omitted, the line length is reset to its previous value.
                   1278: The default setting for terminal output is 78n.
1.51      schwarze 1279: If a sign is given, the line length is added to or subtracted from;
                   1280: otherwise, it is set to the provided value.
1.50      schwarze 1281: Using this request in new manuals is discouraged for several reasons,
                   1282: among others because it overrides the
                   1283: .Xr mandoc 1
                   1284: .Fl O Cm width
                   1285: command line option.
1.79      schwarze 1286: .It Ic \&lnr Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar value Op Ar increment
1.63      schwarze 1287: Set local number register.
                   1288: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1289: .It Ic \&lnrf Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar value Op Ar increment
1.63      schwarze 1290: Set local floating-point register.
                   1291: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1292: .It Ic \&lpfx Ar string
1.63      schwarze 1293: Set a line prefix.
                   1294: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1295: .It Ic \&ls Op Ar factor
1.63      schwarze 1296: Set line spacing.
                   1297: It takes one integer argument specifying the vertical distance of
                   1298: subsequent output text lines measured in v units.
                   1299: Currently ignored.
1.79      schwarze 1300: .It Ic \&lsm Ar macroname
1.63      schwarze 1301: Set a leading spaces trap.
                   1302: This is a groff extension and currently unsupported.
1.79      schwarze 1303: .It Ic \&lt Op Oo Cm + Ns | Ns Cm - Oc Ns Ar width
1.63      schwarze 1304: Set title line length.
                   1305: Currently ignored.
1.79      schwarze 1306: .It Ic \&mc Ar glyph Op Ar dist
1.63      schwarze 1307: Print margin character in the right margin.
1.84      schwarze 1308: The
                   1309: .Ar dist
                   1310: is currently ignored; instead, 1n is used.
1.79      schwarze 1311: .It Ic \&mediasize Ar media
1.63      schwarze 1312: Set the device media size.
                   1313: This is a Heirloom extension and currently ignored.
1.79      schwarze 1314: .It Ic \&minss Ar width
1.63      schwarze 1315: Set minimum word space.
                   1316: This is a Heirloom extension and currently ignored.
1.79      schwarze 1317: .It Ic \&mk Op Ar register
1.63      schwarze 1318: Mark vertical position.
                   1319: Currently ignored.
1.79      schwarze 1320: .It Ic \&mso Ar filename
                   1321: Load a macro file using the search path.
1.63      schwarze 1322: Ignored because insecure.
1.79      schwarze 1323: .It Ic \&na
1.63      schwarze 1324: Disable adjusting without changing the adjustment mode.
                   1325: Currently ignored.
1.79      schwarze 1326: .It Ic \&ne Op Ar height
1.15      kristaps 1327: Declare the need for the specified minimum vertical space
                   1328: before the next trap or the bottom of the page.
1.63      schwarze 1329: Currently ignored.
1.79      schwarze 1330: .It Ic \&nf
1.63      schwarze 1331: Switch to no-fill mode.
                   1332: See
                   1333: .Xr man 7 .
                   1334: Ignored by
1.64      schwarze 1335: .Xr mdoc 7 .
1.79      schwarze 1336: .It Ic \&nh
1.15      kristaps 1337: Turn off automatic hyphenation mode.
1.63      schwarze 1338: Currently ignored.
1.79      schwarze 1339: .It Ic \&nhychar Ar char ...
1.63      schwarze 1340: Define hyphenation-inhibiting characters.
                   1341: This is a Heirloom extension and currently ignored.
1.79      schwarze 1342: .It Ic \&nm Op Ar start Op Ar inc Op Ar space Op Ar indent
1.63      schwarze 1343: Print line numbers.
                   1344: Currently unsupported.
1.79      schwarze 1345: .It Ic \&nn Op Ar number
1.63      schwarze 1346: Temporarily turn off line numbering.
                   1347: Currently unsupported.
1.79      schwarze 1348: .It Ic \&nop Ar body
1.75      schwarze 1349: Execute the rest of the input line as a request or macro line.
1.63      schwarze 1350: Currently unsupported.
1.79      schwarze 1351: .It Ic \&nr Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar expression
1.45      schwarze 1352: Define or change a register.
1.10      kristaps 1353: A register is an arbitrary string value that defines some sort of state,
                   1354: which influences parsing and/or formatting.
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
1.79      schwarze 1363: The following
                   1364: .Ar register
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
1.79      schwarze 1381: .Ic \&Sh
1.17      schwarze 1382: macro will reset this register.
1.10      kristaps 1383: .El
1.79      schwarze 1384: .It Xo
                   1385: .Ic \&nrf Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar expression
                   1386: .Op Ar increment
                   1387: .Xc
1.63      schwarze 1388: Define or change a floating-point register.
                   1389: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1390: .It Ic \&nroff
1.63      schwarze 1391: Force nroff mode.
                   1392: This is a groff extension and currently ignored.
1.79      schwarze 1393: .It Ic \&ns
1.26      schwarze 1394: Turn on no-space mode.
1.63      schwarze 1395: Currently ignored.
1.79      schwarze 1396: .It Ic \&nx Op Ar filename
1.63      schwarze 1397: Abort processing of the current input file and process another one.
                   1398: Ignored because insecure.
1.79      schwarze 1399: .It Ic \&open Ar stream file
1.63      schwarze 1400: Open a file for writing.
                   1401: Ignored because insecure.
1.79      schwarze 1402: .It Ic \&opena Ar stream file
1.63      schwarze 1403: Open a file for appending.
                   1404: Ignored because insecure.
1.79      schwarze 1405: .It Ic \&os
1.63      schwarze 1406: Output saved vertical space.
                   1407: Currently ignored.
1.79      schwarze 1408: .It Ic \&output Ar string
1.63      schwarze 1409: Output directly to intermediate output.
                   1410: Not supported.
1.79      schwarze 1411: .It Ic \&padj Op Cm 1 | 0
1.63      schwarze 1412: Globally control paragraph-at-once adjustment.
                   1413: This is a Heirloom extension and currently ignored.
1.79      schwarze 1414: .It Ic \&papersize Ar media
1.63      schwarze 1415: Set the paper size.
                   1416: This is a Heirloom extension and currently ignored.
1.79      schwarze 1417: .It Ic \&pc Op Ar char
1.63      schwarze 1418: Change the page number character.
                   1419: Currently ignored.
1.79      schwarze 1420: .It Ic \&pev
1.63      schwarze 1421: Print environments.
                   1422: This is a groff extension and currently ignored.
1.79      schwarze 1423: .It Ic \&pi Ar command
1.63      schwarze 1424: Pipe output to a shell command.
                   1425: Ignored because insecure.
1.79      schwarze 1426: .It Ic \&PI
1.63      schwarze 1427: Low-level request used by
1.79      schwarze 1428: .Ic \&BP .
1.63      schwarze 1429: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1430: .It Ic \&pl Op Oo Cm + Ns | Ns Cm - Oc Ns Ar height
1.58      schwarze 1431: Change page length.
1.63      schwarze 1432: Currently ignored.
1.79      schwarze 1433: .It Ic \&pm
                   1434: Print names and sizes of macros, strings, and diversions
                   1435: to standard error output.
1.63      schwarze 1436: Currently ignored.
1.79      schwarze 1437: .It Ic \&pn Oo Cm + Ns | Ns Cm - Oc Ns Ar number
                   1438: Change the page number of the next page.
1.63      schwarze 1439: Currently ignored.
1.79      schwarze 1440: .It Ic \&pnr
                   1441: Print all number registers on standard error output.
1.63      schwarze 1442: Currently ignored.
1.79      schwarze 1443: .It Ic \&po Op Oo Cm + Ns | Ns Cm - Oc Ns Ar offset
1.92      schwarze 1444: Set a horizontal page offset.
                   1445: If no argument is specified, the page offset is reverted to its
                   1446: previous value.
                   1447: If a sign is specified, the new page offset is calculated relative
                   1448: to the current one; otherwise, it is absolute.
                   1449: The argument follows the syntax of
                   1450: .Sx Scaling Widths
                   1451: and the default scaling unit is
                   1452: .Cm m .
1.79      schwarze 1453: .It Ic \&ps Op Oo Cm + Ns | Ns Cm - Oc Ns size
1.26      schwarze 1454: Change point size.
1.63      schwarze 1455: Currently ignored.
1.79      schwarze 1456: .It Ic \&psbb Ar filename
1.63      schwarze 1457: Retrieve the bounding box of a PostScript file.
                   1458: Currently unsupported.
1.79      schwarze 1459: .It Ic \&pshape Ar indent length ...
1.63      schwarze 1460: Set a special shape for the current paragraph.
1.68      schwarze 1461: This is a Heirloom extension and currently unsupported.
1.79      schwarze 1462: .It Ic \&pso Ar command
1.63      schwarze 1463: Include output of a shell command.
                   1464: Ignored because insecure.
1.79      schwarze 1465: .It Ic \&ptr
                   1466: Print the names and positions of all traps on standard error output.
1.63      schwarze 1467: This is a groff extension and currently ignored.
1.79      schwarze 1468: .It Ic \&pvs Op Oo Cm + Ns | Ns Cm - Oc Ns Ar height
1.63      schwarze 1469: Change post-vertical spacing.
                   1470: This is a groff extension and currently ignored.
1.79      schwarze 1471: .It Ic \&rchar Ar glyph ...
1.63      schwarze 1472: Remove glyph definitions.
                   1473: Currently unsupported.
1.79      schwarze 1474: .It Ic \&rd Op Ar prompt Op Ar agument ...
1.63      schwarze 1475: Read from standard input.
                   1476: Currently ignored.
1.79      schwarze 1477: .It Ic \&recursionlimit Ar maxrec maxtail
1.63      schwarze 1478: Set the maximum stack depth for recursive macros.
                   1479: This is a Heirloom extension and currently ignored.
1.79      schwarze 1480: .It Ic \&return Op Ar twice
1.63      schwarze 1481: Exit a macro and return to the caller.
                   1482: Currently unsupported.
1.79      schwarze 1483: .It Ic \&rfschar Ar font glyph ...
1.63      schwarze 1484: Remove font-specific fallback glyph definitions.
                   1485: Currently unsupported.
1.79      schwarze 1486: .It Ic \&rhang Ar font char ... afmunits
1.63      schwarze 1487: Hang characters at right margin.
                   1488: This is a Heirloom extension and currently ignored.
1.79      schwarze 1489: .It Ic \&rj Op Ar N
                   1490: Justify the next
                   1491: .Ar N
                   1492: input lines to the right margin without filling.
1.89      schwarze 1493: .Ar N
                   1494: defaults to 1.
                   1495: An argument of 0 or less ends right adjustment.
1.79      schwarze 1496: .It Ic \&rm Ar macroname
1.52      schwarze 1497: Remove a request, macro or string.
1.79      schwarze 1498: .It Ic \&rn Ar oldname newname
1.63      schwarze 1499: Rename a request, macro, diversion, or string.
1.86      schwarze 1500: In
                   1501: .Xr mandoc 1 ,
                   1502: user-defined macros,
                   1503: .Xr mdoc 7
                   1504: and
                   1505: .Xr man 7
                   1506: macros, and user-defined strings can be renamed, but renaming of
                   1507: predefined strings and of
                   1508: .Nm
                   1509: requests is not supported, and diversions are not implemented at all.
1.79      schwarze 1510: .It Ic \&rnn Ar oldname newname
1.63      schwarze 1511: Rename a number register.
                   1512: Currently unsupported.
1.79      schwarze 1513: .It Ic \&rr Ar register
1.52      schwarze 1514: Remove a register.
1.79      schwarze 1515: .It Ic \&rs
1.63      schwarze 1516: End no-space mode.
                   1517: Currently ignored.
1.79      schwarze 1518: .It Ic \&rt Op Ar dist
1.63      schwarze 1519: Return to marked vertical position.
                   1520: Currently ignored.
1.79      schwarze 1521: .It Ic \&schar Ar glyph Op Ar string
1.63      schwarze 1522: Define global fallback glyph.
                   1523: This is a groff extension and currently unsupported.
1.79      schwarze 1524: .It Ic \&sentchar Ar char ...
1.63      schwarze 1525: Define sentence-ending characters.
                   1526: This is a Heirloom extension and currently ignored.
1.79      schwarze 1527: .It Ic \&shc Op Ar glyph
1.63      schwarze 1528: Change the soft hyphen character.
                   1529: Currently ignored.
1.79      schwarze 1530: .It Ic \&shift Op Ar number
1.63      schwarze 1531: Shift macro arguments.
                   1532: Currently unsupported.
1.79      schwarze 1533: .It Ic \&sizes Ar size ...
1.63      schwarze 1534: Define permissible point sizes.
                   1535: This is a groff extension and currently ignored.
1.79      schwarze 1536: .It Ic \&so Ar filename
1.15      kristaps 1537: Include a source file.
1.79      schwarze 1538: The file is read and its contents processed as input in place of the
                   1539: .Ic \&so
1.15      kristaps 1540: request line.
1.28      kristaps 1541: To avoid inadvertent inclusion of unrelated files,
1.15      kristaps 1542: .Xr mandoc 1
                   1543: only accepts relative paths not containing the strings
                   1544: .Qq ../
                   1545: and
                   1546: .Qq /.. .
1.37      schwarze 1547: .Pp
                   1548: This request requires
                   1549: .Xr man 1
                   1550: to change to the right directory before calling
                   1551: .Xr mandoc 1 ,
                   1552: per convention to the root of the manual tree.
                   1553: Typical usage looks like:
                   1554: .Pp
                   1555: .Dl \&.so man3/Xcursor.3
                   1556: .Pp
                   1557: As the whole concept is rather fragile, the use of
1.79      schwarze 1558: .Ic \&so
1.37      schwarze 1559: is discouraged.
                   1560: Use
                   1561: .Xr ln 1
                   1562: instead.
1.79      schwarze 1563: .It Ic \&sp Op Ar height
1.78      schwarze 1564: Break the output line and emit vertical space.
                   1565: The argument follows the syntax of
                   1566: .Sx Scaling Widths
                   1567: and defaults to one blank line
                   1568: .Pq Li 1v .
1.79      schwarze 1569: .It Ic \&spacewidth Op Cm 1 | 0
1.63      schwarze 1570: Set the space width from the font metrics file.
                   1571: This is a Heirloom extension and currently ignored.
1.79      schwarze 1572: .It Ic \&special Op Ar font ...
1.63      schwarze 1573: Define a special font.
                   1574: This is a groff extension and currently ignored.
1.79      schwarze 1575: .It Ic \&spreadwarn Op Ar width
1.63      schwarze 1576: Warn about wide spacing between words.
                   1577: Currently ignored.
1.79      schwarze 1578: .It Ic \&ss Ar wordspace Op Ar sentencespace
1.63      schwarze 1579: Set space character size.
                   1580: Currently ignored.
1.79      schwarze 1581: .It Ic \&sty Ar position style
1.63      schwarze 1582: Associate style with a font position.
                   1583: This is a groff extension and currently ignored.
1.79      schwarze 1584: .It Ic \&substring Ar stringname startpos Op Ar endpos
1.63      schwarze 1585: Replace a user-defined string with a substring.
                   1586: Currently unsupported.
1.79      schwarze 1587: .It Ic \&sv Op Ar height
1.63      schwarze 1588: Save vertical space.
                   1589: Currently ignored.
1.79      schwarze 1590: .It Ic \&sy Ar command
1.63      schwarze 1591: Execute shell command.
                   1592: Ignored because insecure.
1.79      schwarze 1593: .It Ic \&T&
1.63      schwarze 1594: Re-start a table layout, retaining the options of the prior table
                   1595: invocation.
                   1596: See
                   1597: .Sx \&TS .
1.79      schwarze 1598: .It Ic \&ta Op Ar width ... Op Cm T Ar width ...
1.26      schwarze 1599: Set tab stops.
1.79      schwarze 1600: Each
                   1601: .Ar width
                   1602: argument follows the syntax of
                   1603: .Sx Scaling Widths .
                   1604: If prefixed by a plus sign, it is relative to the previous tab stop.
                   1605: The arguments after the
                   1606: .Cm T
                   1607: marker are used repeatedly as often as needed; for each reuse,
                   1608: they are taken relative to the last previously established tab stop.
                   1609: When
                   1610: .Ic \&ta
                   1611: is called without arguments, all tab stops are cleared.
                   1612: .It Ic \&tc Op Ar glyph
1.75      schwarze 1613: Change tab repetition character.
1.63      schwarze 1614: Currently unsupported.
1.79      schwarze 1615: .It Ic \&TE
1.63      schwarze 1616: End a table context.
                   1617: See
                   1618: .Sx \&TS .
1.80      schwarze 1619: .It Ic \&ti Oo Cm + Ns | Ns Cm - Oc Ns Ar width
                   1620: Break the output line and indent the next output line by
                   1621: .Ar width .
                   1622: If a sign is specified, the temporary indentation is calculated
                   1623: relative to the current indentation; otherwise, it is absolute.
                   1624: The argument follows the syntax of
                   1625: .Sx Scaling Widths
                   1626: and the default scaling unit is
                   1627: .Cm m .
1.79      schwarze 1628: .It Ic \&tkf Ar font minps width1 maxps width2
1.63      schwarze 1629: Enable track kerning for a font.
                   1630: Currently ignored.
1.79      schwarze 1631: .It Ic \&tl No \& Ap Ar left Ap Ar center Ap Ar right Ap
1.63      schwarze 1632: Print a title line.
                   1633: Currently unsupported.
1.79      schwarze 1634: .It Ic \&tm Ar string
1.63      schwarze 1635: Print to standard error output.
                   1636: Currently ignored.
1.79      schwarze 1637: .It Ic \&tm1 Ar string
1.63      schwarze 1638: Print to standard error output, allowing leading blanks.
                   1639: This is a groff extension and currently ignored.
1.79      schwarze 1640: .It Ic \&tmc Ar string
1.63      schwarze 1641: Print to standard error output without a trailing newline.
                   1642: This is a groff extension and currently ignored.
1.79      schwarze 1643: .It Ic \&tr Ar glyph glyph ...
1.6       schwarze 1644: Output character translation.
1.79      schwarze 1645: The first glyph in each pair is replaced by the second one.
                   1646: Character escapes can be used; for example,
1.30      kristaps 1647: .Pp
                   1648: .Dl tr \e(xx\e(yy
                   1649: .Pp
                   1650: replaces all invocations of \e(xx with \e(yy.
1.79      schwarze 1651: .It Ic \&track Ar font minps width1 maxps width2
1.63      schwarze 1652: Static letter space tracking.
                   1653: This is a Heirloom extension and currently ignored.
1.79      schwarze 1654: .It Ic \&transchar Ar char ...
1.63      schwarze 1655: Define transparent characters for sentence-ending.
                   1656: This is a Heirloom extension and currently ignored.
1.79      schwarze 1657: .It Ic \&trf Ar filename
1.63      schwarze 1658: Output the contents of a file, disallowing invalid characters.
                   1659: This is a groff extension and ignored because insecure.
1.79      schwarze 1660: .It Ic \&trimat Ar left top width height
1.63      schwarze 1661: Set the TrimBox page parameter for PDF generation.
                   1662: This is a Heirloom extension and currently ignored.
1.79      schwarze 1663: .It Ic \&trin Ar glyph glyph ...
1.63      schwarze 1664: Output character translation, ignored by
1.79      schwarze 1665: .Ic \&asciify .
1.63      schwarze 1666: Currently unsupported.
1.79      schwarze 1667: .It Ic \&trnt Ar glyph glyph ...
1.63      schwarze 1668: Output character translation, ignored by \e!.
                   1669: Currently unsupported.
1.79      schwarze 1670: .It Ic \&troff
1.63      schwarze 1671: Force troff mode.
                   1672: This is a groff extension and currently ignored.
1.79      schwarze 1673: .It Ic \&TS
1.20      kristaps 1674: Begin a table, which formats input in aligned rows and columns.
1.23      kristaps 1675: See
                   1676: .Xr tbl 7
                   1677: for a description of the tbl language.
1.79      schwarze 1678: .It Ic \&uf Ar font
1.63      schwarze 1679: Globally set the underline font.
                   1680: Currently ignored.
1.79      schwarze 1681: .It Ic \&ul Op Ar N
                   1682: Underline next
                   1683: .Ar N
                   1684: input lines.
1.63      schwarze 1685: Currently ignored.
1.79      schwarze 1686: .It Ic \&unformat Ar divname
1.63      schwarze 1687: Unformat spaces and tabs in a diversion.
                   1688: Currently unsupported.
1.79      schwarze 1689: .It Ic \&unwatch Ar macroname
1.63      schwarze 1690: Disable notification for string or macro.
                   1691: This is a Heirloom extension and currently ignored.
1.79      schwarze 1692: .It Ic \&unwatchn Ar register
1.63      schwarze 1693: Disable notification for register.
                   1694: This is a Heirloom extension and currently ignored.
1.79      schwarze 1695: .It Ic \&vpt Op Cm 1 | 0
1.63      schwarze 1696: Enable or disable vertical position traps.
                   1697: This is a groff extension and currently ignored.
1.79      schwarze 1698: .It Ic \&vs Op Oo Cm + Ns | Ns Cm - Oc Ns Ar height
1.63      schwarze 1699: Change vertical spacing.
                   1700: Currently ignored.
1.79      schwarze 1701: .It Ic \&warn Ar flags
1.63      schwarze 1702: Set warning level.
                   1703: Currently ignored.
1.79      schwarze 1704: .It Ic \&warnscale Ar si
1.63      schwarze 1705: Set the scaling indicator used in warnings.
                   1706: This is a groff extension and currently ignored.
1.79      schwarze 1707: .It Ic \&watch Ar macroname
1.63      schwarze 1708: Notify on change of string or macro.
                   1709: This is a Heirloom extension and currently ignored.
1.79      schwarze 1710: .It Ic \&watchlength Ar maxlength
1.63      schwarze 1711: On change, report the contents of macros and strings
1.75      schwarze 1712: up to the specified length.
1.63      schwarze 1713: This is a Heirloom extension and currently ignored.
1.79      schwarze 1714: .It Ic \&watchn Ar register
1.63      schwarze 1715: Notify on change of register.
                   1716: This is a Heirloom extension and currently ignored.
1.79      schwarze 1717: .It Ic \&wh Ar dist Op Ar macroname
1.63      schwarze 1718: Set a page location trap.
                   1719: Currently unsupported.
1.79      schwarze 1720: .It Ic \&while Ar condition body
1.63      schwarze 1721: Repeated execution while a condition is true.
                   1722: Currently unsupported.
1.79      schwarze 1723: .It Ic \&write Oo \(dq Oc Ns Ar string
1.63      schwarze 1724: Write to an open file.
                   1725: Ignored because insecure.
1.79      schwarze 1726: .It Ic \&writec Oo \(dq Oc Ns Ar string
1.63      schwarze 1727: Write to an open file without appending a newline.
                   1728: Ignored because insecure.
1.79      schwarze 1729: .It Ic \&writem Ar macroname
1.63      schwarze 1730: Write macro or string to an open file.
                   1731: Ignored because insecure.
1.79      schwarze 1732: .It Ic \&xflag Ar level
1.63      schwarze 1733: Set the extension level.
                   1734: This is a Heirloom extension and currently ignored.
1.79      schwarze 1735: .El
1.53      schwarze 1736: .Ss Numerical expressions
                   1737: The
                   1738: .Sx \&nr ,
                   1739: .Sx \&if ,
                   1740: and
                   1741: .Sx \&ie
                   1742: requests accept integer numerical expressions as arguments.
                   1743: These are always evaluated using the C
                   1744: .Vt int
                   1745: type; integer overflow works the same way as in the C language.
                   1746: Numbers consist of an arbitrary number of digits
                   1747: .Sq 0
                   1748: to
                   1749: .Sq 9
                   1750: prefixed by an optional sign
                   1751: .Sq +
                   1752: or
                   1753: .Sq - .
1.67      schwarze 1754: Each number may be followed by one optional scaling unit described below
                   1755: .Sx Scaling Widths .
                   1756: The following equations hold:
                   1757: .Bd -literal -offset indent
                   1758: 1i = 6v = 6P = 10m = 10n = 72p = 1000M = 240u = 240
1.68      schwarze 1759: 254c = 100i = 24000u = 24000
1.67      schwarze 1760: 1f = 65536u = 65536
                   1761: .Ed
1.53      schwarze 1762: .Pp
                   1763: The following binary operators are implemented.
                   1764: Unless otherwise stated, they behave as in the C language:
                   1765: .Pp
                   1766: .Bl -tag -width 2n -compact
                   1767: .It Ic +
                   1768: addition
                   1769: .It Ic -
                   1770: subtraction
                   1771: .It Ic *
                   1772: multiplication
                   1773: .It Ic /
                   1774: division
                   1775: .It Ic %
                   1776: remainder of division
                   1777: .It Ic <
                   1778: less than
                   1779: .It Ic >
                   1780: greater than
                   1781: .It Ic ==
                   1782: equal to
                   1783: .It Ic =
                   1784: equal to, same effect as
                   1785: .Ic ==
                   1786: (this differs from C)
                   1787: .It Ic <=
                   1788: less than or equal to
                   1789: .It Ic >=
                   1790: greater than or equal to
                   1791: .It Ic <>
                   1792: not equal to (corresponds to C
                   1793: .Ic != ;
                   1794: this one is of limited portability, it is supported by Heirloom roff,
                   1795: but not by groff)
                   1796: .It Ic &
                   1797: logical and (corresponds to C
                   1798: .Ic && )
                   1799: .It Ic \&:
                   1800: logical or (corresponds to C
1.87      schwarze 1801: .Ic || )
1.53      schwarze 1802: .It Ic <?
                   1803: minimum (not available in C)
                   1804: .It Ic >?
                   1805: maximum (not available in C)
                   1806: .El
                   1807: .Pp
1.75      schwarze 1808: There is no concept of precedence; evaluation proceeds from left to right,
1.76      schwarze 1809: except when subexpressions are enclosed in parentheses.
1.53      schwarze 1810: Inside parentheses, whitespace is ignored.
1.46      schwarze 1811: .Sh ESCAPE SEQUENCE REFERENCE
                   1812: The
                   1813: .Xr mandoc 1
                   1814: .Nm
                   1815: parser recognises the following escape sequences.
                   1816: Note that the
                   1817: .Nm
                   1818: language defines more escape sequences not implemented in
                   1819: .Xr mandoc 1 .
                   1820: In
                   1821: .Xr mdoc 7
                   1822: and
                   1823: .Xr man 7
                   1824: documents, using escape sequences is discouraged except for those
                   1825: described in the
                   1826: .Sx LANGUAGE SYNTAX
                   1827: section above.
                   1828: .Pp
                   1829: A backslash followed by any character not listed here
                   1830: simply prints that character itself.
                   1831: .Ss \e<newline>
                   1832: A backslash at the end of an input line can be used to continue the
                   1833: logical input line on the next physical input line, joining the text
                   1834: on both lines together as if it were on a single input line.
                   1835: .Ss \e<space>
                   1836: The escape sequence backslash-space
                   1837: .Pq Sq \e\ \&
                   1838: is an unpaddable space-sized non-breaking space character; see
                   1839: .Sx Whitespace .
                   1840: .Ss \e\(dq
                   1841: The rest of the input line is treated as
                   1842: .Sx Comments .
                   1843: .Ss \e%
                   1844: Hyphenation allowed at this point of the word; ignored by
                   1845: .Xr mandoc 1 .
                   1846: .Ss \e&
                   1847: Non-printing zero-width character; see
                   1848: .Sx Whitespace .
                   1849: .Ss \e\(aq
                   1850: Acute accent special character; use
                   1851: .Sq \e(aa
                   1852: instead.
                   1853: .Ss \e( Ns Ar cc
                   1854: .Sx Special Characters
                   1855: with two-letter names, see
                   1856: .Xr mandoc_char 7 .
                   1857: .Ss \e*[ Ns Ar name ]
                   1858: Interpolate the string with the
                   1859: .Ar name ;
                   1860: see
                   1861: .Sx Predefined Strings
                   1862: and
                   1863: .Sx ds .
                   1864: For short names, there are variants
                   1865: .No \e* Ns Ar c
                   1866: and
                   1867: .No \e*( Ns Ar cc .
1.74      schwarze 1868: .Ss \e,
                   1869: Left italic correction (groff extension); ignored by
                   1870: .Xr mandoc 1 .
1.46      schwarze 1871: .Ss \e-
                   1872: Special character
                   1873: .Dq mathematical minus sign .
1.74      schwarze 1874: .Ss \e/
                   1875: Right italic correction (groff extension); ignored by
                   1876: .Xr mandoc 1 .
1.46      schwarze 1877: .Ss \e[ Ns Ar name ]
                   1878: .Sx Special Characters
                   1879: with names of arbitrary length, see
                   1880: .Xr mandoc_char 7 .
                   1881: .Ss \e^
                   1882: One-twelfth em half-narrow space character, effectively zero-width in
                   1883: .Xr mandoc 1 .
                   1884: .Ss \e`
                   1885: Grave accent special character; use
                   1886: .Sq \e(ga
                   1887: instead.
                   1888: .Ss \e{
                   1889: Begin conditional input; see
                   1890: .Sx if .
                   1891: .Ss \e\(ba
                   1892: One-sixth em narrow space character, effectively zero-width in
                   1893: .Xr mandoc 1 .
                   1894: .Ss \e}
                   1895: End conditional input; see
                   1896: .Sx if .
                   1897: .Ss \e~
                   1898: Paddable non-breaking space character.
                   1899: .Ss \e0
                   1900: Digit width space character.
                   1901: .Ss \eA\(aq Ns Ar string Ns \(aq
                   1902: Anchor definition; ignored by
                   1903: .Xr mandoc 1 .
                   1904: .Ss \eB\(aq Ns Ar string Ns \(aq
1.54      schwarze 1905: Interpolate
                   1906: .Sq 1
                   1907: if
1.46      schwarze 1908: .Ar string
1.54      schwarze 1909: conforms to the syntax of
                   1910: .Sx Numerical expressions
                   1911: explained above and
                   1912: .Sq 0
                   1913: otherwise.
1.46      schwarze 1914: .Ss \eb\(aq Ns Ar string Ns \(aq
                   1915: Bracket building function; ignored by
                   1916: .Xr mandoc 1 .
                   1917: .Ss \eC\(aq Ns Ar name Ns \(aq
                   1918: .Sx Special Characters
                   1919: with names of arbitrary length.
                   1920: .Ss \ec
1.60      schwarze 1921: When encountered at the end of an input text line,
                   1922: the next input text line is considered to continue that line,
                   1923: even if there are request or macro lines in between.
                   1924: No whitespace is inserted.
1.46      schwarze 1925: .Ss \eD\(aq Ns Ar string Ns \(aq
                   1926: Draw graphics function; ignored by
                   1927: .Xr mandoc 1 .
                   1928: .Ss \ed
                   1929: Move down by half a line; ignored by
                   1930: .Xr mandoc 1 .
                   1931: .Ss \ee
                   1932: Backslash special character.
                   1933: .Ss \eF[ Ns Ar name ]
                   1934: Switch font family (groff extension); ignored by
                   1935: .Xr mandoc 1 .
                   1936: For short names, there are variants
                   1937: .No \eF Ns Ar c
                   1938: and
                   1939: .No \eF( Ns Ar cc .
                   1940: .Ss \ef[ Ns Ar name ]
                   1941: Switch to the font
                   1942: .Ar name ,
                   1943: see
                   1944: .Sx Text Decoration .
                   1945: For short names, there are variants
                   1946: .No \ef Ns Ar c
                   1947: and
                   1948: .No \ef( Ns Ar cc .
                   1949: .Ss \eg[ Ns Ar name ]
                   1950: Interpolate the format of a number register; ignored by
                   1951: .Xr mandoc 1 .
                   1952: For short names, there are variants
                   1953: .No \eg Ns Ar c
                   1954: and
                   1955: .No \eg( Ns Ar cc .
                   1956: .Ss \eH\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
                   1957: Set the height of the current font; ignored by
                   1958: .Xr mandoc 1 .
1.93    ! schwarze 1959: .Ss \eh\(aq Ns Oo Cm \&| Oc Ns Ar width Ns \(aq
        !          1960: Horizontal motion.
        !          1961: If the vertical bar is given, the motion is relative to the current
        !          1962: indentation.
        !          1963: Otherwise, it is relative to the current position.
1.81      schwarze 1964: The default scaling unit is
                   1965: .Cm m .
1.46      schwarze 1966: .Ss \ek[ Ns Ar name ]
                   1967: Mark horizontal input place in register; ignored by
                   1968: .Xr mandoc 1 .
                   1969: For short names, there are variants
                   1970: .No \ek Ns Ar c
                   1971: and
                   1972: .No \ek( Ns Ar cc .
                   1973: .Ss \eL\(aq Ns Ar number Ns Oo Ar c Oc Ns \(aq
                   1974: Vertical line drawing function; ignored by
                   1975: .Xr mandoc 1 .
1.82      schwarze 1976: .Ss \el\(aq Ns Ar width Ns Oo Ar c Oc Ns \(aq
                   1977: Draw a horizontal line of
                   1978: .Ar width
                   1979: using the glyph
                   1980: .Ar c .
1.46      schwarze 1981: .Ss \eM[ Ns Ar name ]
                   1982: Set fill (background) color (groff extension); ignored by
                   1983: .Xr mandoc 1 .
                   1984: For short names, there are variants
                   1985: .No \eM Ns Ar c
                   1986: and
                   1987: .No \eM( Ns Ar cc .
                   1988: .Ss \em[ Ns Ar name ]
                   1989: Set glyph drawing color (groff extension); ignored by
                   1990: .Xr mandoc 1 .
                   1991: For short names, there are variants
                   1992: .No \em Ns Ar c
                   1993: and
                   1994: .No \em( Ns Ar cc .
                   1995: .Ss \eN\(aq Ns Ar number Ns \(aq
                   1996: Character
                   1997: .Ar number
                   1998: on the current font.
                   1999: .Ss \en[ Ns Ar name ]
                   2000: Interpolate the number register
                   2001: .Ar name .
                   2002: For short names, there are variants
                   2003: .No \en Ns Ar c
                   2004: and
                   2005: .No \en( Ns Ar cc .
                   2006: .Ss \eo\(aq Ns Ar string Ns \(aq
1.66      schwarze 2007: Overstrike, writing all the characters contained in the
1.65      schwarze 2008: .Ar string
                   2009: to the same output position.
                   2010: In terminal and HTML output modes,
                   2011: only the last one of the characters is visible.
1.88      schwarze 2012: .Ss \ep
                   2013: Break the output line at the end of the current word.
1.46      schwarze 2014: .Ss \eR\(aq Ns Ar name Oo +|- Oc Ns Ar number Ns \(aq
                   2015: Set number register; ignored by
                   2016: .Xr mandoc 1 .
                   2017: .Ss \eS\(aq Ns Ar number Ns \(aq
                   2018: Slant output; ignored by
                   2019: .Xr mandoc 1 .
                   2020: .Ss \es\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
                   2021: Change point size; ignored by
                   2022: .Xr mandoc 1 .
                   2023: Alternative forms
                   2024: .No \es Ns Oo +|- Oc Ns Ar n ,
                   2025: .No \es Ns Oo +|- Oc Ns \(aq Ns Ar number Ns \(aq ,
                   2026: .No \es Ns [ Oo +|- Oc Ns Ar number ] ,
                   2027: and
                   2028: .No \es Ns Oo +|- Oc Ns [ Ar number Ns ]
                   2029: are also parsed and ignored.
                   2030: .Ss \et
                   2031: Horizontal tab; ignored by
                   2032: .Xr mandoc 1 .
                   2033: .Ss \eu
                   2034: Move up by half a line; ignored by
                   2035: .Xr mandoc 1 .
                   2036: .Ss \eV[ Ns Ar name ]
                   2037: Interpolate an environment variable; ignored by
                   2038: .Xr mandoc 1 .
                   2039: For short names, there are variants
                   2040: .No \eV Ns Ar c
                   2041: and
                   2042: .No \eV( Ns Ar cc .
                   2043: .Ss \ev\(aq Ns Ar number Ns \(aq
                   2044: Vertical motion; ignored by
                   2045: .Xr mandoc 1 .
                   2046: .Ss \ew\(aq Ns Ar string Ns \(aq
                   2047: Interpolate the width of the
1.54      schwarze 2048: .Ar string .
                   2049: The
                   2050: .Xr mandoc 1
                   2051: implementation assumes that after expansion of user-defined strings, the
                   2052: .Ar string
                   2053: only contains normal characters, no escape sequences, and that each
                   2054: character has a width of 24 basic units.
1.46      schwarze 2055: .Ss \eX\(aq Ns Ar string Ns \(aq
                   2056: Output
                   2057: .Ar string
                   2058: as device control function; ignored in nroff mode and by
                   2059: .Xr mandoc 1 .
                   2060: .Ss \ex\(aq Ns Ar number Ns \(aq
                   2061: Extra line space function; ignored by
                   2062: .Xr mandoc 1 .
                   2063: .Ss \eY[ Ns Ar name ]
                   2064: Output a string as a device control function; ignored in nroff mode and by
                   2065: .Xr mandoc 1 .
                   2066: For short names, there are variants
                   2067: .No \eY Ns Ar c
                   2068: and
                   2069: .No \eY( Ns Ar cc .
                   2070: .Ss \eZ\(aq Ns Ar string Ns \(aq
                   2071: Print
                   2072: .Ar string
                   2073: with zero width and height; ignored by
                   2074: .Xr mandoc 1 .
                   2075: .Ss \ez
1.71      schwarze 2076: Output the next character without advancing the cursor position.
1.2       kristaps 2077: .Sh COMPATIBILITY
1.69      schwarze 2078: The
                   2079: .Xr mandoc 1
                   2080: implementation of the
1.17      schwarze 2081: .Nm
1.69      schwarze 2082: language is intentionally incomplete.
                   2083: Unimplemented features include:
1.2       kristaps 2084: .Pp
                   2085: .Bl -dash -compact
1.56      kristaps 2086: .It
1.69      schwarze 2087: For security reasons,
                   2088: .Xr mandoc 1
                   2089: never reads or writes external files except via
                   2090: .Sx \&so
                   2091: requests with safe relative paths.
                   2092: .It
                   2093: There is no automatic hyphenation, no adjustment to the right margin,
                   2094: and no centering; the output is always set flush-left.
                   2095: .It
                   2096: Support for setting tabulator positions
                   2097: and tabulator and leader characters is missing,
                   2098: and support for manually changing indentation is limited.
                   2099: .It
1.56      kristaps 2100: The
                   2101: .Sq u
                   2102: scaling unit is the default terminal unit.
1.69      schwarze 2103: In traditional troff systems, this unit changes depending on the
1.56      kristaps 2104: output media.
1.10      kristaps 2105: .It
1.69      schwarze 2106: Width measurements are implemented in a crude way
                   2107: and often yield wrong results.
                   2108: Explicit movement requests and escapes are ignored.
                   2109: .It
                   2110: There is no concept of output pages, no support for floats,
                   2111: graphics drawing, and picture inclusion;
                   2112: terminal output is always continuous.
                   2113: .It
                   2114: Requests regarding color, font families, and glyph manipulation
                   2115: are ignored.
                   2116: Font support is very limited.
                   2117: Kerning is not implemented, and no ligatures are produced.
1.27      kristaps 2118: .It
1.10      kristaps 2119: The
1.69      schwarze 2120: .Qq \(aq
                   2121: macro control character does not suppress output line breaks.
1.2       kristaps 2122: .It
1.69      schwarze 2123: Diversions are not implemented,
                   2124: and support for traps is very incomplete.
1.4       kristaps 2125: .It
1.69      schwarze 2126: While recursion is supported,
                   2127: .Sx \&while
                   2128: loops are not.
1.2       kristaps 2129: .El
1.69      schwarze 2130: .Pp
                   2131: The special semantics of the
                   2132: .Cm nS
                   2133: number register is an idiosyncracy of
                   2134: .Ox
                   2135: manuals and not supported by other
                   2136: .Xr mdoc 7
                   2137: implementations.
1.17      schwarze 2138: .Sh SEE ALSO
                   2139: .Xr mandoc 1 ,
1.27      kristaps 2140: .Xr eqn 7 ,
1.17      schwarze 2141: .Xr man 7 ,
                   2142: .Xr mandoc_char 7 ,
1.23      kristaps 2143: .Xr mdoc 7 ,
                   2144: .Xr tbl 7
1.17      schwarze 2145: .Rs
                   2146: .%A Joseph F. Ossanna
                   2147: .%A Brian W. Kernighan
                   2148: .%I AT&T Bell Laboratories
                   2149: .%T Troff User's Manual
                   2150: .%R Computing Science Technical Report
                   2151: .%N 54
                   2152: .%C Murray Hill, New Jersey
                   2153: .%D 1976 and 1992
                   2154: .%U http://www.kohala.com/start/troff/cstr54.ps
                   2155: .Re
                   2156: .Rs
                   2157: .%A Joseph F. Ossanna
                   2158: .%A Brian W. Kernighan
                   2159: .%A Gunnar Ritter
                   2160: .%T Heirloom Documentation Tools Nroff/Troff User's Manual
                   2161: .%D September 17, 2007
                   2162: .%U http://heirloom.sourceforge.net/doctools/troff.pdf
                   2163: .Re
                   2164: .Sh HISTORY
1.35      kristaps 2165: The RUNOFF typesetting system, whose input forms the basis for
1.17      schwarze 2166: .Nm ,
1.35      kristaps 2167: was written in MAD and FAP for the CTSS operating system by Jerome E.
                   2168: Saltzer in 1964.
                   2169: Doug McIlroy rewrote it in BCPL in 1969, renaming it
                   2170: .Nm .
                   2171: Dennis M. Ritchie rewrote McIlroy's
1.36      schwarze 2172: .Nm
                   2173: in PDP-11 assembly for
1.35      kristaps 2174: .At v1 ,
                   2175: Joseph F. Ossanna improved roff and renamed it nroff
                   2176: for
                   2177: .At v2 ,
                   2178: then ported nroff to C as troff, which Brian W. Kernighan released with
                   2179: .At v7 .
                   2180: In 1989, James Clarke re-implemented troff in C++, naming it groff.
1.1       kristaps 2181: .Sh AUTHORS
1.15      kristaps 2182: .An -nosplit
1.31      kristaps 2183: This
1.1       kristaps 2184: .Nm
                   2185: reference was written by
1.41      schwarze 2186: .An Kristaps Dzonsons Aq Mt kristaps@bsd.lv
1.15      kristaps 2187: and
1.41      schwarze 2188: .An Ingo Schwarze Aq Mt schwarze@openbsd.org .

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