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groff_char(7)       Miscellaneous Information Manual       groff_char(7)

Name         top

       groff_char - GNU roff special character and glyph repertoire

Description         top

       The GNU roff typesetting system has a large glyph repertoire
       suitable for production of varied literary, professional,
       technical, and mathematical documents.  However, its input
       character set is restricted to that defined by the standards ISO
       Latin-1 (ISO 8859-1) and IBM code page 1047 (an arrangement of
       EBCDIC).  For ease of document maintenance in UTF-8 environments,
       it is advisable to use only the Unicode basic Latin code points,
       a subset of all of the foregoing historically referred to as
       US-ASCII, which has only 94 visible, printable code points.

       AT&T troff in the 1970s faced a similar problem of typesetter
       devices with a glyph repertoire differing from that of the
       computers that controlled them.  The solution troff adopted was a
       form of escape sequence known as a special character to access
       several dozen additional glyphs available in the fonts prepared
       for mounting in the phototypesetter.  These glyphs were mapped
       onto a two-character name space for a degree of mnemonic
       convenience; for example, the escape sequence \(aa encoded an
       acute accent and \(sc a section sign.  (Characters that don't
       require an escape sequence for their expression, like “a”, are
       termed “ordinary”.)

       As in other respects, groff has removed historical roff
       limitations on the lengths of special character escapes, but
       recognizes and retains compatibility with the historical names.
       groff expands the lexicon of glyphs available by name and permits
       users to define their own special character escapes with the
       .char request.

       This document lists all of the glyph names predefined by groff
       and describes the systematic notation by which it enables access
       to arbitrary Unicode code points and construction of composite
       glyphs.  The glyphs listed in this document may not be available,
       or may vary in appearance, depending on the output driver chosen
       when the page was rendered (with the -T option to the man(1) or
       roff programs).  The driver used in generation of this page was
       “utf8”.

       A few escape sequences that are not groff special characters also
       produce glyphs; these exist for syntactical or historical
       reasons.  \', \`, \-, and \_ are translated on input to the
       special characters \[aq], \[ga], \[-], and \[ul], respectively.
       Others include \\, \. (backslash-dot), and \e; see groff(7).  A
       small number of special characters represent glyphs that are not
       encoded in Unicode; examples include the baseline rule \[ru] and
       the Bell Systems logo \[bs].

       In groff, you can test output driver support for any character
       (ordinary or special) with the conditional expression operator
       “c”.
              .ie c \[bs] \{Welcome to the \[bs] Bell System;
              did you get the Wehrmacht helmet or the Death Star?\}
              .el No Bell Systems logo.

       For brevity in the remainder of this document, we shall refer to
       systems conforming to the ISO 646:1991 IRV, ISO 8859, or ISO
       10646 (“Unicode”) character encoding standards as “ISO” systems,
       and those employing IBM code page 1047 as “EBCDIC” systems.  That
       said, EBCDIC systems that support groff are known to also support
       UTF-8.

       While groff accepts eight-bit encoded input, not all such code
       points are valid as input.  On ISO platforms, character codes 0,
       11, 13–31, and 128–159 are invalid.  (This is all C0 and C1
       controls except for SOH through LF [Control+A to Control+J], and
       FF [Control+L].)  On EBCDIC platforms, 0, 8–9, 11, 13–20, 23–31,
       and 48–63 are invalid.  Some of these code points are used by
       groff for internal purposes, which is one reason it does not
       support UTF-8 natively.

   Fundamental character set
       The ninety-four characters catalogued above, plus the space, tab,
       and newline, form the fundamental character set for groff input;
       anything in the language, even over one million code points in
       Unicode, can be expressed using it.  On ISO systems, code points
       in the range 33–126 comprise a common set of printable glyphs in
       all of the aforementioned ISO character encoding standards.  It
       is this character set and (with some noteworthy exceptions) the
       corresponding glyph repertoire for which AT&T troff was
       implemented.  On EBCDIC systems, printable characters are in the
       range 66–201 and 203–254; those without counterparts in the ISO
       range 33–126 are discussed in the next subsection.

       All of the following characters map to glyphs as you would
       expect.

          ┌──────────────────────────────────────────────────────────┐
          │! # $ % & ( ) * + , . / 0 1 2 3 4 5 6 7 8 9 : ; < = > ? @ │
          │A B C D E F G H I J K L M N O P Q R S T U V W X Y Z [ ] _ │
          │a b c d e f g h i j k l m n o p q r s t u v w x y z { | } │
          └──────────────────────────────────────────────────────────┘
       The remaining seven of the ninety-four code points in this range
       surprise computing professionals and others intimately familiar
       with the ISO character encodings.  The developers of AT&T troff
       chose mappings for them that would be useful for typesetting
       technical literature in a broad range of scientific disciplines;
       the preparation of AT&T's patent filings with the U.S. government
       was the application of the system that “paid the bills” at the
       Bell Labs site where troff and Unix were first developed.  It is
       also worth noting that the prevailing character encoding standard
       in the 1970s, USAS X3.4-1968 (“ASCII”) deliberately supported
       semantic ambiguity at some code points, and outright substitution
       at several others, to suit the localization demands of various
       national standards bodies.

       The table below presents the seven exceptional code points with
       their typical keycap engravings, their glyph mappings and
       semantics in roff systems, and the escapes producing the Unicode
       basic Latin character they replace.  The first, the neutral
       double quote, is a partial exception because it does represent
       itself, but since it is also used by roff systems to quote macro
       arguments, groff supports a special character escape as an
       alternative form so that the glyph can be easily included in
       macro arguments without requiring the user to master the quoting
       rules that AT&T troff required in that context.  Furthermore, not
       all of the special character escapes are portable to AT&T troff
       and all of its descendants; these groff extensions are presented
       using its special character escape form \[], whereas portable
       special character escapes are shown in the traditional \( form.
       \- and \e are portable to all known troffs.  \e means “the glyph
       of the current escape character”; it therefore can produce
       unexpected output if the .ec or .eo requests are used.  On
       devices with a limited glyph repertoire, the appearances of
       glyphs on the same row of the table may be identical; except for
       the neutral double quote, this will not be the case on more-
       capable devices.  Review your document using as many different
       postprocessors as possible.

       ┌────────────────────────────────────────────────────────────────┐
       │Keycap   Appearance and meaning   Special character and meaning │
       ├────────────────────────────────────────────────────────────────┤
       │"        " neutral double quote   \[dq] neutral double quote    │
       │'        ’ closing single quote   \[aq] neutral apostrophe      │
       │-        - hyphen                 \- or \[-] minus sign         │
       │\        (escape character)       \e or \[rs] reverse solidus   │
       │^        ˆ modifier circumflex    \(ha circumflex/caret/“hat”   │
       │`        ‘ single opening quote   \(ga grave accent             │
       │~        ˜ modifier tilde         \(ti tilde                    │
       └────────────────────────────────────────────────────────────────┘
       The hyphen-minus is a particularly unfortunate case of
       overloading.  Its awkward name in ISO 8859 and later standards
       reflects the many conflicting purposes to which it had already
       been put in the 1980s, including a hyphen, a minus sign, and
       (alone or in repetition) dashes of varying widths.  For best
       results in groff, use the “-” character in input without an
       escape only to mean a hyphen, as in the phrase “long-term”.  For
       a minus sign in running text or a Unix command-line option dash,
       use \- (or \[-] in groff if you find it helps the clarity of the
       source document).  (Another minus sign, for use in mathematical
       equations, is available as \[mi]).  AT&T troff supported em-
       dashes as \(em, as does groff.

       The special character escape for the apostrophe as a neutral
       single quote is typically needed only in technical content;
       typing words like “can't” and “Anne's” in a natural way will
       render correctly, because in ordinary prose an apostrophe is
       typeset either as a closing single quotation mark or as a neutral
       single quote, depending on the capabilities of the output device.
       By contrast, special character escapes should be used for
       quotation marks unless portability to limited or historical troff
       implementations is necessary; on those systems, the input
       convention is to pair the grave accent with the apostrophe for
       single quotes, and to double both characters for double quotes.
       AT&T troff defined no special characters for quotation marks or
       the apostrophe.  Repeated single quotes (‘‘thus’’) will be
       visually distinguishable from double quotes (“thus”) on terminal
       devices, and perhaps on others (depending on the font selected).

       ┌────────────────────────────────────────────────────────────────┐
       │AT&T troff input          recommended groff input               │
       ├────────────────────────────────────────────────────────────────┤
       │A Winter's Tale           A Winter's Tale                       │
       │`U.K. outer quotes'       \[oq]U.K. outer quotes\[cq]           │
       │`U.K. ``inner'' quotes'   \[oq]U.K. \[lq]inner\[rq] quotes\[cq] │
       │``U.S. outer quotes''     \[lq]U.S. outer quotes\[rq]           │
       │``U.S. `inner' quotes''   \[lq]U.S. \[oq]inner\[cq] quotes\[rq] │
       └────────────────────────────────────────────────────────────────┘
       If you expect to use quotation marks frequently in your document,
       see if the macro package you're using defines strings or macros
       to facilitate quotation.

       Using Unicode basic Latin characters to compose boxes and lines
       is ill-advised.  roff systems have special characters for drawing
       straight horizontal and vertical lines; see subsection “Rules and
       lines” below.  Preprocessors like tbl(1) and pic(1) draw boxes
       and will produce the best possible output for the device, falling
       back to basic Latin glyphs only when necessary.

   Eight-bit encodings and Latin-1 supplement
       ISO 646 is a seven-bit code encoding 128 code points; eight-bit
       codes are twice the size.  ISO 8859-1 and code page 1047
       allocated the additional space to what Unicode calls “C1
       controls” (control characters) and the “Latin-1 supplement”.  The
       C1 controls are neither printable nor usable as groff input.

       Two characters in the Latin-1 supplement are handled specially.
       troff never produces them as output.

       NBSP   encodes the no-break space.  On input it is mapped to \~,
              the adjustable non-breaking space escape.

       SHY    encodes the soft hyphen character.  On input it is mapped
              to \%, the hyphenation control escape.

       The remaining characters in the Latin-1 supplement represent
       themselves.  Although they can be specified directly with the
       keyboard on systems configured to use Latin-1 as the character
       encoding, it is more portable, both to other roff systems and to
       UTF-8 environments, to use their glyph names, shown below.

       ¡  \[r!] inverted exclamation mark     Ñ  \[~N] N tilde
       ¢  \[ct] cent sign                     Ò  \[`O] O grave
       £  \[Po] pound sign                    Ó  \['O] O acute
       ¤  \[Cs] currency sign                 Ô  \[^O] O circumflex
       ¥  \[Ye] yen sign                      Õ  \[~O] O tilde
       ¦  \[bb] broken bar                    Ö  \[:O] O dieresis
       §  \[sc] section sign                  ×  \[mu] multiplication sign
       ¨  \[ad] dieresis accent               Ø  \[/O] O slash
       ©  \[co] copyright sign                Ù  \[`U] U grave
       ª  \[Of] feminine ordinal indicator    Ú  \['U] U acute
       «  \[Fo] left double chevron           Û  \[^U] U circumflex
       ¬  \[no] logical not                   Ü  \[:U] U dieresis
       ®  \[rg] registered sign               Ý  \['Y] Y acute
       ¯  \[a-] macron accent                 Þ  \[TP] uppercase thorn
       °  \[de] degree sign                   ß  \[ss] lowercase sharp s
       ±  \[+-] plus-minus                    à  \[`a] a grave
       ²  \[S2] superscript two               á  \['a] a acute
       ³  \[S3] superscript three             â  \[^a] a circumflex
       ´  \[aa] acute accent                  ã  \[~a] a tilde
       µ  \[mc] micro sign                    ä  \[:a] a dieresis
       ¶  \[ps] pilcrow sign                  å  \[oa] a ring
       ·  \[pc] centered period               æ  \[ae] ae ligature
       ¸  \[ac] cedilla accent                ç  \[,c] c cedilla
       ¹  \[S1] superscript one               è  \[`e] e grave
       º  \[Om] masculine ordinal indicator   é  \['e] e acute
       »  \[Fc] right double chevron          ê  \[^e] e circumflex
       ¼  \[14] one quarter symbol            ë  \[:e] e dieresis
       ½  \[12] one half symbol               ì  \[`i] i grave
       ¾  \[34] three quarters symbol         í  \['i] e acute
       ¿  \[r?] inverted question mark        î  \[^i] i circumflex
       À  \[`A] A grave                       ï  \[:i] i dieresis
       Á  \['A] A acute                       ð  \[Sd] lowercase eth
       Â  \[^A] A circumflex                  ñ  \[~n] n tilde
       Ã  \[~A] A tilde                       ò  \[`o] o grave
       Ä  \[:A] A dieresis                    ó  \['o] o acute
       Å  \[oA] A ring                        ô  \[^o  o circumflex
       Æ  \[AE] AE ligature                   õ  \[~o] o tilde
       Ç  \[,C] C cedilla                     ö  \[:o] o dieresis
       È  \[`E] E grave                       ÷  \[di] division sign
       É  \['E] E acute                       ø  \[/o] o slash
       Ê  \[^E] E circumflex                  ù  \[`u] u grave
       Ë  \[:E] E dieresis                    ú  \['u] u acute
       Ì  \[`I] I grave                       û  \[^u] u circumflex
       Í  \['I] I acute                       ü  \[:u] u dieresis
       Î  \[^I] I circumflex                  ý  \['y] y acute
       Ï  \[:I] I dieresis                    þ  \[Tp] lowercase thorn
       Ð  \[-D] uppercase eth                 ÿ  \[:y] y dieresis

   Special character escape forms
       Glyphs that lack a character code in the basic Latin repertoire
       to directly represent them are entered by one of several special
       character escape forms.  Such glyphs can be simple or composite,
       and accessed either by name or numerically by code point.  Code
       points and combining properties are determined by character
       encoding standards, whereas glyph names originated in AT&T troff
       special character escapes.  Glyph names are not limited to
       alphanumeric characters; any of the printable characters from the
       Unicode basic Latin repertoire may be used.

       \(gl   is a special character escape for the glyph with the two-
              character name gl.  This is the syntax form supported by
              AT&T troff.  The acute accent, \(aa, is an example.

       \[glyph-name]
              is a special character escape for glyph-name, which can be
              of arbitrary length.  The foregoing acute accent example
              could be expressed in groff as \[aa].

              An ordinary input character “c” is not the same as \[c];
              the latter is internally mapped to glyph name “\c”.  In
              other words, “\[a]” is not “a”, but rather \a, the
              uninterpreted leader escape sequence.  By default, groff
              defines a single glyph name of length one, namely the
              minus sign, which can be accessed as either \- or \[-].

       \[base-glyph composite-1 composite-2 ... composite-n]
              is a composite glyph.  Glyphs like a lowercase “e” with an
              acute accent, as in the word “café”, can be expressed as
              \[e aa].  See subsection “Accents” below for a table of
              combining glyph names.

       Unicode encodes far more characters than groff has glyph names
       for; special character escape forms based on numerical code
       points enable access to any of them.  Frequently used glyphs or
       glyph combinations can be stored in strings, and new glyph names
       can be created with the .char request, enabling the user to
       devise ad hoc names for them; see groff(7).

       \[unnnn[n[n]]]
              is a Unicode numeric special character escape.  With this
              form, any Unicode point can be indicated using four to six
              hexadecimal digits, with hexadecimal letters accepted in
              uppercase form only.  Thus, \[u02DA] accesses the
              (spacing) ring accent, producing “˚”.

       Unicode code points can be composed as well; when they are, troff
       requires NFD (Normalization Form D), where all Unicode glyphs are
       maximally decomposed.  (Exception: precomposed characters in the
       Latin-1 supplement described above are also accepted.  Do not
       count on this exception remaining in a future troff that accepts
       UTF-8 input directly.)  Thus, troff accepts “caf\['e]”,
       “caf\[e aa]”, and “caf\[u0065_0301]”, as ways to input “café”.
       (Due to its legacy 8-bit encoding compatibility, at present it
       also accepts “caf\[u00E9]” on ISO Latin-1 systems.)

       \[ubase-glyph[_combining-component]...]
              constructs a composite glyph from Unicode numeric special
              character escapes.  The code points of the base glyph and
              the combining components are each expressed in
              hexadecimal, with an underscore (_) separating each
              component.  Thus, \[u0065_0301] produces “é”.

       \[charnnn]
              expresses an eight-bit code point where nnn is the code
              point of the character, a decimal number between 0 and 255
              without leading zeroes.  This legacy numeric special
              character escape is used to map characters onto glyphs via
              the .trin request in macro files loaded by grotty(1).

Glyph tables         top

       In this section, groff's glyph name repertoire is presented in
       tabular form.  The meanings of the columns are as follows.

       Output  shows the glyph as it appears on the device used to
               render this document; although it can have a notably
               different shape on other devices (and is subject to user-
               directed translation and replacement), groff attempts
               reasonable equivalency on all output devices.

       Input   shows the groff character (ordinary or special) that
               normally produces the glyph.  Some code points have
               multiple glyph names.

       Unicode is the code point notation for the glyph or combining
               glyph sequence as described in subsection “Special
               character escape forms” above.  It corresponds to the
               standard notation for Unicode short identifiers such that
               groff's unnnn is equivalent to Unicode's U+nnnn.

       Notes   describes the glyph, elucidating the mnemonic value of
               the glyph name where possible.

               A plus sign “+” indicates that the glyph name appears in
               the AT&T troff user's manual, CSTR #54 (1992 revision).
               When using the AT&T special character syntax \(xx,
               widespread portability can be expected from such names.

               Entries marked with “***” denote glyphs used for
               mathematical purposes.  On typesetter devices, such
               glyphs are typically drawn from a special font (see
               groff_font(5)).  Often, such glyphs have metrics which
               look incongruous in normal text.  A few which are not
               uncommon in running text have “text variants”, which
               should work better in that context.  Conversely, a
               handful of glyphs that are normally drawn from a regular
               font are required in mathematical text.  Both sets of
               exceptions are noted in the tables where they appear
               (“Logical symbols” and “Mathematical symbols”).

   Basic Latin
       Apart from basic Latin characters with special mappings,
       described in subsection “Fundamental character set” above, a few
       others in that range have special character glyph names.  These
       were defined for ease of input on non-U.S. keyboards lacking
       keycaps for them, or for symmetry with other special character
       glyph names serving a similar purpose.

       The vertical bar is overloaded; the \[ba] and \[or] escapes may
       render differently.  See subsection “Mathematical symbols” below
       for special variants of the plus, minus, and equals signs
       normally drawn from this range.

       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       "        \[dq]   u0022     neutral double quote
       #        \[sh]   u0023     number sign
       $        \[Do]   u0024     dollar sign
       '        \[aq]   u0027     apostrophe, neutral single quote
       /        \[sl]   u002F     slash, solidus +
       @        \[at]   u0040     at sign
       [        \[lB]   u005B     left square bracket

       \        \[rs]   u005C     reverse solidus
       ]        \[rB]   u005D     right square bracket
       ^        \[ha]   u005E     circumflex, caret, “hat” +
       {        \[lC]   u007B     left brace
       |        |       u007C     bar
       |        \[ba]   u007C     bar
       |        \[or]   u007C     bitwise or +
       }        \[rC]   u007D     right brace
       ~        \[ti]   u007E     tilde +

   Supplementary Latin letters
       Historically, \[ss] could be considered a ligature of “sz”.  An
       uppercase form is available as \[u1E9E], but in the German
       language it is of specialized use; ß does not normally uppercase-
       transform to it, but rather to “SS”.  “Lowercase f with hook” is
       also used as a function symbol; see subsection “Mathematical
       symbols” below.

       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       Ð        \[-D]   u00D0     uppercase eth
       ð        \[Sd]   u00F0     lowercase eth
       Þ        \[TP]   u00DE     uppercase thorn
       þ        \[Tp]   u00FE     lowercase thorn
       ß        \[ss]   u00DF     lowercase sharp s
       ı        \[.i]   u0131     i without tittle
       ȷ        \[.j]   u0237     j without tittle
       ƒ        \[Fn]   u0192     lowercase f with hook, function

   Ligatures and digraphs
       Output   Input   Unicode           Notes
       ──────────────────────────────────────────────────────────────────
       ff       \[ff]   u0066_0066        ff ligature +
       fi       \[fi]   u0066_0069        fi ligature +
       fl       \[fl]   u0066_006C        fl ligature +
       ffi      \[Fi]   u0066_0066_0069   ffi ligature +
       ffl      \[Fl]   u0066_0066_006C   ffl ligature +
       Æ        \[AE]   u00C6             AE ligature
       æ        \[ae]   u00E6             ae ligature
       Π       \[OE]   u0152             OE ligature
       œ        \[oe]   u0153             oe ligature
       IJ        \[IJ]   u0132             IJ digraph
       ij        \[ij]   u0133             ij digraph
       Ł        \[/L]   u0141             L with stroke
       ł        \[/l]   u0142             l with stroke
       Ø        \[/O]   u00D8             O with stroke
       ø        \[/o]   u00F8             o with stroke

   Accented characters
       All of these glyphs can be composed using combining glyph names
       as described in subsection “Special character escape forms”
       above; the names below can be thought of convenient short
       aliases.

       Output   Input   Unicode      Notes
       ──────────────────────────────────────────────────────────────────
       Á        \['A]   u0041_0301   A acute
       Ć        \['C]   u0043_0301   C acute
       É        \['E]   u0045_0301   E acute
       Í        \['I]   u0049_0301   I acute
       Ó        \['O]   u004F_0301   O acute
       Ú        \['U]   u0055_0301   U acute
       Ý        \['Y]   u0059_0301   Y acute
       á        \['a]   u0061_0301   a acute
       ć        \['c]   u0063_0301   c acute
       é        \['e]   u0065_0301   e acute

       í        \['i]   u0069_0301   i acute
       ó        \['o]   u006F_0301   o acute
       ú        \['u]   u0075_0301   u acute
       ý        \['y]   u0079_0301   y acute

       Ä        \[:A]   u0041_0308   A dieresis
       Ë        \[:E]   u0045_0308   E dieresis
       Ï        \[:I]   u0049_0308   I dieresis
       Ö        \[:O]   u004F_0308   O dieresis
       Ü        \[:U]   u0055_0308   U dieresis
       Ÿ        \[:Y]   u0059_0308   Y dieresis
       ä        \[:a]   u0061_0308   a dieresis
       ë        \[:e]   u0065_0308   e dieresis
       ï        \[:i]   u0069_0308   i dieresis
       ö        \[:o]   u006F_0308   o dieresis
       ü        \[:u]   u0075_0308   u dieresis
       ÿ        \[:y]   u0079_0308   y dieresis

       Â        \[^A]   u0041_0302   A circumflex
       Ê        \[^E]   u0045_0302   E circumflex
       Î        \[^I]   u0049_0302   I circumflex
       Ô        \[^O]   u004F_0302   O circumflex
       Û        \[^U]   u0055_0302   U circumflex
       â        \[^a]   u0061_0302   a circumflex
       ê        \[^e]   u0065_0302   e circumflex
       î        \[^i]   u0069_0302   i circumflex
       ô        \[^o]   u006F_0302   o circumflex
       û        \[^u]   u0075_0302   u circumflex

       À        \[`A]   u0041_0300   A grave
       È        \[`E]   u0045_0300   E grave
       Ì        \[`I]   u0049_0300   I grave
       Ò        \[`O]   u004F_0300   O grave
       Ù        \[`U]   u0055_0300   U grave
       à        \[`a]   u0061_0300   a grave
       è        \[`e]   u0065_0300   e grave
       ì        \[`i]   u0069_0300   i grave
       ò        \[`o]   u006F_0300   o grave
       ù        \[`u]   u0075_0300   u grave

       Ã        \[~A]   u0041_0303   A tilde
       Ñ        \[~N]   u004E_0303   N tilde
       Õ        \[~O]   u004F_0303   O tilde
       ã        \[~a]   u0061_0303   a tilde
       ñ        \[~n]   u006E_0303   n tilde
       õ        \[~o]   u006F_0303   o tilde

       Š        \[vS]   u0053_030C   S caron
       š        \[vs]   u0073_030C   s caron
       Ž        \[vZ]   u005A_030C   Z caron
       ž        \[vz]   u007A_030C   z caron

       Ç        \[,C]   u0043_0327   C cedilla
       ç        \[,c]   u0063_0327   c cedilla

       Å        \[oA]   u0041_030A   A ring
       å        \[oa]   u0061_030A   a ring

   Accents
       The .composite request is used to map the accents to code points
       with non-spacing semantics; the values given in parentheses are
       their spacing counterparts.

       Output   Input   Unicode         Notes
       ──────────────────────────────────────────────────────────────────
       ˝        \[a"]   u030B (u02DD)   double acute accent

       ¯        \[a-]   u0304 (u00AF)   macron accent
       ˙        \[a.]   u0307 (u02D9)   dot accent
       ^        \[a^]   u0302 (u005E)   circumflex accent
       ´        \[aa]   u0301 (u00B4)   acute accent +
       `        \[ga]   u0300 (u0060)   grave accent +
       ˘        \[ab]   u0306 (u02D8)   breve accent
       ¸        \[ac]   u0327 (u00B8)   cedilla accent
       ¨        \[ad]   u0308 (u00A8)   dieresis accent
       ˇ        \[ah]   u030C (u02C7)   caron accent
       ˚        \[ao]   u030A (u02DA)   ring accent
       ~        \[a~]   u0303 (u007E)   tilde accent
       ˛        \[ho]   u0328 (u02DB)   hook accent

   Quotation marks
       The neutral double quote, often useful when documenting
       programming languages, is also available as a special character
       for convenience when including it in macro arguments; see
       subsection “Fundamental character set” above.

       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       „        \[Bq]   u201E     low double comma quote
       ‚        \[bq]   u201A     low single comma quote
       “        \[lq]   u201C     left double quote
       ”        \[rq]   u201D     right double quote
       ‘        \[oq]   u2018     single opening (left) quote
       ’        \[cq]   u2019     single closing (right) quote
       '        \[aq]   u0027     apostrophe, neutral single quote
       "        "       u0022     neutral double quote
       "        \[dq]   u0022     neutral double quote
       «        \[Fo]   u00AB     left double chevron
       »        \[Fc]   u00BB     right double chevron
       ‹        \[fo]   u2039     left single chevron
       ›        \[fc]   u203A     right single chevron

   Punctuation
       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       ¡        \[r!]   u00A1     inverted exclamation mark
       ¿        \[r?]   u00BF     inverted question mark
       —        \[em]   u2014     em-dash +
       –        \[en]   u2013     en-dash
       ‐        \[hy]   u2010     hyphen +

   Brackets
       On typestter devices, the bracket extensions are font-invariant
       glyphs; that is, they are rendered the same way regardless of
       font (with a drawing escape sequence).  On terminals, they are
       not font-invariant; groff maps them rather arbitrarily to U+23AA
       (“curly bracket extension”).  In AT&T troff, only one glyph was
       available to vertically extend brackets, braces, and parentheses:
       \(bv.

       Not all devices supply bracket pieces that can be piled up with
       \b due to the restrictions of the escape's piling algorithm.  A
       general solution to build brackets out of pieces is the following
       macro:
              .\" Make a pile centered vertically 0.5em above the baseline.
              .\" The first argument is placed at the top.
              .\" The pile is returned in string 'pile'.
              .eo
              .de pile-make
              .  nr pile-wd 0
              .  nr pile-ht 0
              .  ds pile-args
              .
              .  nr pile-# \n[.$]
              .  while \n[pile-#] \{\
              .    nr pile-wd (\n[pile-wd] >? \w'\$[\n[pile-#]]')
              .    nr pile-ht +(\n[rst] - \n[rsb])
              .    as pile-args \v'\n[rsb]u'\"
              .    as pile-args \Z'\$[\n[pile-#]]'\"
              .    as pile-args \v'-\n[rst]u'\"
              .    nr pile-# -1
              .  \}
              .
              .  ds pile \v'(-0.5m + (\n[pile-ht]u / 2u))'\"
              .  as pile \*[pile-args]\"
              .  as pile \v'((\n[pile-ht]u / 2u) + 0.5m)'\"
              .  as pile \h'\n[pile-wd]u'\"
              ..
              .ec

       Another complication is the fact that some glyphs which represent
       bracket pieces in AT&T troff can be used for other mathematical
       symbols as well, for example \(lf and \(rf which provide the
       floor operator.  Some output postprocessors, such as grodvi(1),
       don't unify such glyphs.  For this reason, the four glyphs \[lf],
       \[rf], \[lc], and \[rc], are not unified with similar-looking
       bracket pieces.  In groff, only glyphs with long names are
       guaranteed to pile up correctly for all devices—provided those
       glyphs exist.

       Output   Input               Unicode   Notes
       ──────────────────────────────────────────────────────────────────────
       [        [                   u005B     left square bracket
       [        \[lB]               u005B     left square bracket
       ]        ]                   u005D     right square bracket
       ]        \[rB]               u005D     right square bracket
       {        {                   u007B     left brace
       {        \[lC]               u007B     left brace
       }        }                   u007D     right brace
       }        \[rC]               u007D     right brace
       ⟨        \[la]               u27E8     left angle bracket
       ⟩        \[ra]               u27E9     right angle bracket
       ⎪        \[bv]               u23AA     brace vertical extension + ***
       ⎪        \[braceex]          u23AA     brace vertical extension

       ⎡        \[bracketlefttp]    u23A1     left square bracket top
       ⎢        \[bracketleftex]    u23A2     left square bracket extension
       ⎣        \[bracketleftbt]    u23A3     left square bracket bottom

       ⎤        \[bracketrighttp]   u23A4     right square bracket top
       ⎥        \[bracketrightex]   u23A5     right square bracket extension
       ⎦        \[bracketrightbt]   u23A6     right square bracket bottom

       ⎧        \[lt]               u23A7     left brace top +
       ⎨        \[lk]               u23A8     left brace middle +
       ⎩        \[lb]               u23A9     left brace bottom +
       ⎧        \[bracelefttp]      u23A7     left brace top
       ⎨        \[braceleftmid]     u23A8     left brace middle
       ⎩        \[braceleftbt]      u23A9     left brace bottom
       ⎪        \[braceleftex]      u23AA     left brace extension

       ⎫        \[rt]               u23AB     right brace top +
       ⎬        \[rk]               u23AC     right brace middle +
       ⎭        \[rb]               u23AD     right brace bottom +
       ⎫        \[bracerighttp]     u23AB     right brace top
       ⎬        \[bracerightmid]    u23AC     right brace middle
       ⎭        \[bracerightbt]     u23AD     right brace bottom
       ⎪        \[bracerightex]     u23AA     right brace extension

       ⎛        \[parenlefttp]      u239B     left parenthesis top

       ⎜        \[parenleftex]      u239C     left parenthesis extension
       ⎝        \[parenleftbt]      u239D     left parenthesis bottom
       ⎞        \[parenrighttp]     u239E     right parenthesis top
       ⎟        \[parenrightex]     u239F     right parenthesis extension
       ⎠        \[parenrightbt]     u23A0     right parenthesis bottom

   Arrows
       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       ←        \[<-]   u2190     horizontal arrow left +
       →        \[->]   u2192     horizontal arrow right +
       ↔        \[<>]   u2194     bidirectional horizontal arrow
       ↓        \[da]   u2193     vertical arrow down +
       ↑        \[ua]   u2191     vertical arrow up +
       ↕        \[va]   u2195     bidirectional vertical arrow
       ⇐        \[lA]   u21D0     horizontal double arrow left
       ⇒        \[rA]   u21D2     horizontal double arrow right
       ⇔        \[hA]   u21D4     bidirectional horizontal double arrow
       ⇓        \[dA]   u21D3     vertical double arrow down
       ⇑        \[uA]   u21D1     vertical double arrow up
       ⇕        \[vA]   u21D5     bidirectional vertical double arrow
       ⎯        \[an]   u23AF     horizontal arrow extension

   Rules and lines
       On typesetter devices, the font-invariant glyphs (see subsection
       “Brackets” above) \[br], \[ul], and \[rn] form corners when
       adjacent; they can be used to build boxes.  On terminal devices,
       they are mapped as shown in the table.  The Unicode-derived names
       of these three glyphs are approximations.

       The input character _ always accesses the underscore glyph in a
       font; \[ul], by contrast, may be font-invariant on typesetter
       devices.

       The baseline rule \[ru] is a font-invariant glyph, namely a rule
       of one-half em.

       \[rn] also appears in subsection “Mathematical symbols” below.

       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       |        |       u007C     bar
       |        \[ba]   u007C     bar
       │        \[br]   u2502     box rule +
       _        _       u005F     underscore, low line +
       _        \[ul]   u005F     underscore, low line +
       ‾        \[rn]   u203E     radical extension, overline +
       _        \[ru]   ---       baseline rule +
       ¦        \[bb]   u00A6     broken bar
       /        /       u002F     slash, solidus +
       /        \[sl]   u002F     slash, solidus +
       \        \[rs]   u005C     reverse solidus

   Text markers
       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       ○        \[ci]   u25CB     circle +
       •        \[bu]   u2022     bullet +
       †        \[dg]   u2020     dagger +
       ‡        \[dd]   u2021     double dagger +
       ◊        \[lz]   u25CA     lozenge, diamond
       □        \[sq]   u25A1     square +
       ¶        \[ps]   u00B6     pilcrow sign
       §        \[sc]   u00A7     section sign +
       ☜        \[lh]   u261C     hand pointing left +
       ☞        \[rh]   u261E     hand pointing right +

       @        @       u0040     at sign
       @        \[at]   u0040     at sign
       #        #       u0023     number sign
       #        \[sh]   u0023     number sign
       ↵        \[CR]   u21B5     carriage return
       ✓        \[OK]   u2713     check mark

   Legal symbols
       The Bell Systems logo is not supported in groff.

       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       ©        \[co]   u00A9     copyright sign +
       ®        \[rg]   u00AE     registered sign +
       ™        \[tm]   u2122     trade mark sign
                \[bs]   ---       Bell Systems logo +

   Currency symbols
       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       $        $       u0024     dollar sign
       $        \[Do]   u0024     dollar sign
       ¢        \[ct]   u00A2     cent sign +
       €        \[eu]   u20AC     Euro sign
       €        \[Eu]   u20AC     variant Euro sign
       ¥        \[Ye]   u00A5     yen sign
       £        \[Po]   u00A3     pound sign
       ¤        \[Cs]   u00A4     currency sign

   Units
       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       °        \[de]   u00B0     degree sign +
       ‰        \[%0]   u2030     per thousand, per mille sign
       ′        \[fm]   u2032     arc minute sign +
       ″        \[sd]   u2033     arc second sign
       µ        \[mc]   u00B5     micro sign
       ª        \[Of]   u00AA     feminine ordinal indicator
       º        \[Om]   u00BA     masculine ordinal indicator

   Logical symbols
       Whether the two variants of the not sign differ in appearance or
       spacing will depend on the device and font selected.

       Output   Input    Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       ∧        \[AN]    u2227     logical and
       ∨        \[OR]    u2228     logical or
       ¬        \[no]    u00AC     logical not + ***
       ¬        \[tno]   u00AC     text variant of \[no]
       ∃        \[te]    u2203     there exists
       ∀        \[fa]    u2200     for all
       ∋        \[st]    u220B     such that
       ∴        \[3d]    u2234     therefore
       ∴        \[tf]    u2234     therefore
       |        |        u007C     bitwise or +
       |        \[or]    u007C     bitwise or +

   Mathematical symbols
       \[Fn] also appears in subsection “Supplementary Latin letters”
       above.  Observe the two varieties of the plus-minus,
       multiplication, and division signs; \[+-], \[mu], and \[di] are
       normally drawn from the special font, but have regular (“text”)
       font variants.  Also be aware of three glyphs available in
       special font variants that are normally drawn from regular fonts:
       the plus, minus, and equals signs.  Whether these variants differ
       in appearance or spacing will depend on the device and font
       selected.

       In AT&T troff, \(rn served as the horizontal extension of the
       radical (square root) sign, \(sr.  In groff, you can use
       \[radicalex] instead of \[rn] for continuation of the radical
       sign \[sr]; these have text metrics.  \[sqrt] and \[sqrtex] are
       their counterparts with mathematical spacing.

       Output   Input          Unicode      Notes
       ─────────────────────────────────────────────────────────────────────
       ½        \[12]          u00BD        one half symbol +
       ¼        \[14]          u00BC        one quarter symbol +
       ¾        \[34]          u00BE        three quarters symbol +
       ⅛        \[18]          u215B        one eighth symbol
       ⅜        \[38]          u215C        three eighths symbol
       ⅝        \[58]          u215D        five eighths symbol
       ⅞        \[78]          u215E        seven eighths symbol
       ¹        \[S1]          u00B9        superscript one
       ²        \[S2]          u00B2        superscript two
       ³        \[S3]          u00B3        superscript three

       +        +              u002B        plus
       +        \[pl]          u002B        special variant of plus + ***
       -        \[-]           u002D        minus
       −        \[mi]          u2212        special variant of minus + ***
       ∓        \[-+]          u2213        minus-plus
       ±        \[+-]          u00B1        plus-minus + ***
       ±        \[t+-]         u00B1        text variant of \[+-]
       ·        \[pc]          u00B7        centered period
       ⋅        \[md]          u22C5        multiplication dot
       ×        \[mu]          u00D7        multiplication sign + ***
       ×        \[tmu]         u00D7        text variant of \[mu]
       ⊗        \[c*]          u2297        circled times
       ⊕        \[c+]          u2295        circled plus
       ÷        \[di]          u00F7        division sign + ***
       ÷        \[tdi]         u00F7        text variant of \[di]
       ⁄        \[f/]          u2044        fraction slash
       ∗        \[**]          u2217        mathematical asterisk +

       ≤        \[<=]          u2264        less than or equal to +
       ≥        \[>=]          u2265        greater than or equal to +
       ≪        \[<<]          u226A        much less than
       ≫        \[>>]          u226B        much greater than
       =        =              u003D        equals
       =        \[eq]          u003D        special variant of equals + ***
       ≠        \[!=]          u003D_0338   not equals +
       ≡        \[==]          u2261        equivalent +
       ≢        \[ne]          u2261_0338   not equivalent
       ≅        \[=~]          u2245        approximately equal to
       ≃        \[|=]          u2243        asymptotically equal to +
       ∼        \[ap]          u223C        similar to, tilde operator +
       ≈        \[~~]          u2248        almost equal to
       ≈        \[~=]          u2248        almost equal to
       ∝        \[pt]          u221D        proportional to +

       ∅        \[es]          u2205        empty set +
       ∈        \[mo]          u2208        element of a set +
       ∉        \[nm]          u2208_0338   not element of set
       ⊂        \[sb]          u2282        proper subset +
       ⊄        \[nb]          u2282_0338   not subset
       ⊃        \[sp]          u2283        proper superset +
       ⊅        \[nc]          u2283_0338   not superset
       ⊆        \[ib]          u2286        subset or equal +
       ⊇        \[ip]          u2287        superset or equal +
       ∩        \[ca]          u2229        intersection, cap +
       ∪        \[cu]          u222A        union, cup +

       ∠        \[/_]          u2220        angle
       ⊥        \[pp]          u22A5        perpendicular
       ∫        \[is]          u222B        integral +
       ∫        \[integral]    u222B        integral ***
       ∑        \[sum]         u2211        summation ***
       ∏        \[product]     u220F        product ***
       ∐        \[coproduct]   u2210        coproduct ***
       ∇        \[gr]          u2207        gradient +
       √        \[sr]          u221A        radical sign, square root +
       ‾        \[rn]          u203E        radical extension, overline +
                \[radicalex]   ---          radical extension
       √        \[sqrt]        u221A        radical sign, square root ***
                \[sqrtex]      ---          radical extension ***

       ⌈        \[lc]          u2308        left ceiling +
       ⌉        \[rc]          u2309        right ceiling +
       ⌊        \[lf]          u230A        left floor +
       ⌋        \[rf]          u230B        right floor +

       ∞        \[if]          u221E        infinity +
       ℵ        \[Ah]          u2135        aleph symbol
       ƒ        \[Fn]          u0192        lowercase f with hook, function
       ℑ        \[Im]          u2111        blackletter I, imaginary part
       ℜ        \[Re]          u211C        blackletter R, real part
       ℘        \[wp]          u2118        Weierstrass p
       ∂        \[pd]          u2202        partial differential
       ℏ        \[-h]          u210F        h bar
       ℏ        \[hbar]        u210F        h bar

   Greek glyphs
       These glyphs are intended for technical use, not for typesetting
       Greek language text; normally, the uppercase letters have upright
       shape, and the lowercase ones are slanted.

       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       Α        \[*A]   u0391     uppercase alpha +
       Β        \[*B]   u0392     uppercase beta +
       Γ        \[*G]   u0393     uppercase gamma +
       Δ        \[*D]   u0394     uppercase delta +
       Ε        \[*E]   u0395     uppercase epsilon +
       Ζ        \[*Z]   u0396     uppercase zeta +
       Η        \[*Y]   u0397     uppercase eta +
       Θ        \[*H]   u0398     uppercase theta +
       Ι        \[*I]   u0399     uppercase iota +
       Κ        \[*K]   u039A     uppercase kappa +
       Λ        \[*L]   u039B     uppercase lambda +
       Μ        \[*M]   u039C     uppercase mu +
       Ν        \[*N]   u039D     uppercase nu +
       Ξ        \[*C]   u039E     uppercase xi +
       Ο        \[*O]   u039F     uppercase omicron +
       Π        \[*P]   u03A0     uppercase pi +
       Ρ        \[*R]   u03A1     uppercase rho +
       Σ        \[*S]   u03A3     uppercase sigma +
       Τ        \[*T]   u03A4     uppercase tau +
       Υ        \[*U]   u03A5     uppercase upsilon +
       Φ        \[*F]   u03A6     uppercase phi +
       Χ        \[*X]   u03A7     uppercase chi +
       Ψ        \[*Q]   u03A8     uppercase psi +
       Ω        \[*W]   u03A9     uppercase omega +

       α        \[*a]   u03B1     lowercase alpha +
       β        \[*b]   u03B2     lowercase beta +
       γ        \[*g]   u03B3     lowercase gamma +
       δ        \[*d]   u03B4     lowercase delta +

       ε        \[*e]   u03B5     lowercase epsilon +
       ζ        \[*z]   u03B6     lowercase zeta +
       η        \[*y]   u03B7     lowercase eta +
       θ        \[*h]   u03B8     lowercase theta +
       ι        \[*i]   u03B9     lowercase iota +
       κ        \[*k]   u03BA     lowercase kappa +
       λ        \[*l]   u03BB     lowercase lambda +
       μ        \[*m]   u03BC     lowercase mu +
       ν        \[*n]   u03BD     lowercase nu +
       ξ        \[*c]   u03BE     lowercase xi +
       ο        \[*o]   u03BF     lowercase omicron +
       π        \[*p]   u03C0     lowercase pi +
       ρ        \[*r]   u03C1     lowercase rho +
       ς        \[ts]   u03C2     terminal lowercase sigma +
       σ        \[*s]   u03C3     lowercase sigma +
       τ        \[*t]   u03C4     lowercase tau +
       υ        \[*u]   u03C5     lowercase upsilon +
       ϕ        \[*f]   u03D5     lowercase phi +
       χ        \[*x]   u03C7     lowercase chi +
       ψ        \[*q]   u03C8     lowercase psi +
       ω        \[*w]   u03C9     lowercase omega +

       ϑ        \[+h]   u03D1     variant theta
       φ        \[+f]   u03C6     variant phi (curly shape)
       ϖ        \[+p]   u03D6     variant pi (similar to omega)
       ϵ        \[+e]   u03F5     variant epsilon (lunate)

   Playing card symbols
       Output   Input   Unicode   Notes
       ──────────────────────────────────────────────────────────────────
       ♣        \[CL]   u2663     solid club suit
       ♠        \[SP]   u2660     solid spade suit
       ♥        \[HE]   u2665     solid heart suit
       ♦        \[DI]   u2666     solid diamond suit

Authors         top

       This document was written by James Clark ⟨jjc@jclark.com⟩, with
       additions by Werner Lemberg ⟨wl@gnu.org⟩ and Bernd Warken
       ⟨groff-bernd.warken-72@web.de⟩, revised to use tbl(1) by Eric S.
       Raymond ⟨esr@thyrsus.com⟩, and largely rewritten by G. Branden
       Robinson ⟨g.branden.robinson@gmail.com⟩.

See also         top

       Groff: The GNU Implementation of troff, by Trent A. Fisher and
       Werner Lemberg, is the primary groff manual.  Section “Using
       Symbols” may be of particular note.  You can browse it
       interactively with “info '(groff) Using Symbols'”.

       “An extension to the troff character set for Europe”, E.G.
       Keizer, K.J. Simonsen, J. Akkerhuis; EUUG Newsletter, Volume 9,
       No. 2, Summer 1989

       The Unicode Standard ⟨http://www.unicode.org⟩

       “7-bit Character Sets” 
       ⟨https://www.aivosto.com/articles/charsets-7bit.html⟩ by Tuomas
       Salste documents the inherent ambiguity and configurability (in
       terms of variable code points) of the ASCII encoding standard.

       groff_rfc1345(7) describes an alternative set of special
       character glyph names, which extends and in some cases overrides
       the definitions listed above.

       groff(1), troff(1), groff(7)

COLOPHON         top

       This page is part of the groff (GNU troff) project.  Information
       about the project can be found at 
       ⟨http://www.gnu.org/software/groff/⟩.  If you have a bug report
       for this manual page, see ⟨http://www.gnu.org/software/groff/⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://git.savannah.gnu.org/git/groff.git⟩ on 2021-06-20.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2021-06-17.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

groff 1.23.0.rc1.654-4e1db-dirt1y6 June 2021                 groff_char(7)

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