2 .\" The above line should force the use of eqn as a preprocessor
6 Last update : 05 July 2002
8 This file is part of groff, the GNU roff type-setting system.
9 It is the source of the man-page groff_diff(7).
11 Copyright (C) 1989, 2001, 2002 Free Software Foundation, Inc.
12 written by James Clark
14 modified by Werner Lemberg <wl@gnu.org>
15 Bernd Warken <bwarken@mayn.de>
17 Permission is granted to copy, distribute and/or modify this document
18 under the terms of the GNU Free Documentation License, Version 1.1 or
19 any later version published by the Free Software Foundation; with the
20 Invariant Sections being this .ig-section and AUTHORS, with no
21 Front-Cover Texts, and with no Back-Cover Texts.
23 A copy of the Free Documentation License is included as a file called
24 FDL in the main directory of the groff source package.
27 .\" --------------------------------------------------------------------
29 .\" --------------------------------------------------------------------
43 .\" define a string tx for the TeX logo
44 .ie t .ds tx T\h'-.1667m'\v'.224m'E\v'-.224m'\h'-.125m'X
48 .\" --------------------------------------------------------------------
49 .\" start of macro definitions
71 .\" Text \[oq]\f[CB]\*[@arg1]\f[]\[cq]\$*
72 . Text \[oq]\f[B]\*[@arg1]\f[]\[cq]\$*
75 .c A shell command line
78 . IR "shell#" "\h'1m'\f[CB]\$*\f[]\/"
80 .c reference of a request or macro
84 .\" Text \f[CB]\*[@arg1]\f[]\$*
85 . Text \f[B]\*[@arg1]\f[]\$*
90 .c representation of an escape sequence
94 .\" Text \f[CB]\[rs]\*[@arg1]\f[]\$*
95 . Text \f[B]\[rs]\*[@arg1]\&\f[]\$*
99 .\" end of macro definitions
101 .\" from old groff_out.man
108 .\" --------------------------------------------------------------------
110 .\" --------------------------------------------------------------------
112 .TH GROFF_DIFF @MAN7EXT@ "@MDATE@" "Groff Version @VERSION@"
114 groff_diff \- differences between GNU troff and classical troff
117 .\" --------------------------------------------------------------------
119 .\" --------------------------------------------------------------------
121 This manual page describes the language differences between
125 text processing system and the classical
127 formatter of the freely available Unix\~7 of the 1970s, documented in
129 .I Troff User's Manual
134 This inludes the roff language as well as the intermediate output
135 format (troff output).
140 gives pointers to both the classical
147 At the moment, this document is the place of the most actual
148 documentation within the
152 This might change in the future.
154 Actually, all novelties of the groff language are first described here
155 and will pervade into the other documents only at a later stage.
158 .\" --------------------------------------------------------------------
160 .\" --------------------------------------------------------------------
162 In this section, all additional features of
164 compared to the classical Unix\~7
166 are described in detail.
169 .\" --------------------------------------------------------------------
171 .\" --------------------------------------------------------------------
173 The names of number registers, fonts, strings/\:macros/\:diversions,
174 special characters, and colors can be of any length.
176 In escape sequences, additionally to the classical
178 construction for a two character name, you can use
180 for a name of arbitrary length, for example in
182 .TP \w'\[rs]f[xxx]'u+3n
184 Print the special character called
194 is a new syntax equal to
196 i.e., to return to the previous font.
199 .BI \[rs]*[ "xxx arg1 arg2 .\|.\|." ]
210 Interpolate number register
214 .\" --------------------------------------------------------------------
215 .SS "Fractional pointsizes"
216 .\" --------------------------------------------------------------------
228 There is a new scale indicator
230 that has the effect of multiplying by sizescale.
232 Requests and escape sequences in troff interpret arguments that
233 represent a pointsize as being in units of scaled points, but they
234 evaluate each such argument using a default scale indicator of
236 Arguments treated in this way are the argument to the
238 request, the third argument to the
240 request, the second and fourth arguments to the
242 request, the argument to the
244 escape sequence, and those variants of the
246 escape sequence that take a numeric expression as their argument.
249 For example, suppose sizescale is 1000; then a scaled point will be
250 equivalent to a millipoint; the call
254 and so sets the pointsize to 10250 scaled points, which is equal to
260 returns the pointsize in points as decimal fraction.
262 There is also a new number register
264 that returns the pointsize in scaled points.
267 It would make no sense to use the
269 scale indicator in a numeric expression whose default scale indicator
278 Similarly it would make no sense to use a scaling indicator other than
282 in a numeric expression whose default scale indicator was
286 disallows this as well.
289 There is also new scale indicator\~\c
291 which multiplies by the number of units in a scaled point.
297 Be sure not to confuse the
304 .\" --------------------------------------------------------------------
305 .SS "Numeric expressions"
306 .\" --------------------------------------------------------------------
308 Spaces are permitted in a number expression within parentheses.
312 indicates a scale of 100ths of an em.
314 indicates a scale of 65536 units, providing fractions for color
319 For example, 0.5f = 32768u.
341 as the default scaling indicator.
345 is missing, ignore scaling indicators in the evaluation of
349 .\" --------------------------------------------------------------------
350 .SS "New escape sequences"
351 .\" --------------------------------------------------------------------
354 .BI \[rs]A' anything '
359 resp., depending on whether
361 is or is not acceptable as the name of a string, macro, diversion, number
362 register, environment, font, or color.
369 This is useful if you want to lookup user input in some sort of
373 .BI \[rs]B' anything '
378 resp., depending on whether
380 is or is not a valid numeric expression.
390 Typeset character named
392 Normally it is more convenient to use
393 .BI \[rs][ xxx ]\f[R].
396 has the advantage that it is compatible with recent versions of
398 and is available in compatibility mode.
402 This is equivalent to an escape character, but it is not interpreted in
405 For example, strings to start and end superscripting could be defined
411 .Text .ds { \[rs]v'\-.3m'\[rs]s'\[rs]En[.s]*6u/10u'
413 .Text .ds } \[rs]s0\[rs]v'.3m'
419 ensures that these definitions will work even if
421 gets interpreted in copy-mode (for example, by being used in a macro
433 This is the same as the
438 switches back to the previous color (note that
440 won't work; it selects font family `P' instead).
450 switches back to the previous color.
458 Set background color for filled objects drawn with the
459 .BI \[rs]D' .\|.\|. '
462 switches back to the previous color.
466 Typeset the character with code
472 Most devices only have characters with codes between 0 and 255.
474 If the current font does not contain a character with that code,
481 escape sequence can be conveniently used in conjunction with the
488 .Text .char \[rs][phone] \[rs]f(ZD\[rs]N'37'
493 The code of each character is given in the fourth column in the font
494 description file after the
498 It is possible to include unnamed characters in the font description
499 file by using a name of
503 escape sequence is the only way to use these.
509 Suppressing troff output.
517 are intended for internal use by
523 Disable any ditroff glyphs from being emitted to the device driver,
524 provided that the escape occurs at the outer level (see
531 Enable output of glyphs, provided that the escape occurs at the outer
537 also reset the registers
545 These four registers mark the top left and bottom right hand corners
546 of a box which encompasses all written glyphs.
550 Provided that the escape occurs at the outer level, enable output of
551 glyphs and also write out to stderr the page number and four registers
552 encompassing the glyphs previously written since the last call to
557 Begin a nesting level.
563 This is really an internal mechanism for
565 while producing images.
567 They are generated by running the troff source through
569 to the postscript device and
571 to produce images in PNG format.
575 escape will start a new page if the device is not html (to reduce the
576 possibility of images crossing a page boundary).
583 .BI \[rs]O5[ Pfilename ]
588 Provided that this escape occurs at the outer nesting level, write
592 The position of the image,
594 must be specified and must be one of l, r, c, or i (left, right,
598 will be associated with the production of the next inline image.
602 .BI \[rs]R' name\ \[+-]n '
603 This has the same effect as
607 .BI .nr\ name\ \[+-]n
614 Set the point size to
618 must be exactly two digits.
628 Set the point size to
632 is a numeric expression with a default scale indicator of\~\c
641 Interpolate the contents of the environment variable
646 is interpreted in copy-mode.
654 This is approximately equivalent to
655 .BI \[rs]X'\[rs]*[ xxx ]'\f[R].
656 However the contents of the string or macro
658 are not interpreted; also it is permitted for
660 to have been defined as a macro and thus contain newlines (it is not
661 permitted for the argument to
663 to contain newlines).
665 The inclusion of newlines requires an extension to the UNIX troff
666 output format, and will confuse drivers that do not know about this
670 .BI \[rs]Z' anything '
671 Print anything and then restore the horizontal and vertical position;
673 may not contain tabs or leaders.
677 The name by which the current macro was invoked.
681 request can make a macro have more than one name.
685 In a macro or string, the concatenation of all the arguments separated
690 In a macro or string, the concatenation of all the arguments with each
691 surrounded by double quotes, and separated by spaces.
697 In a macro or string, this gives the
703 Macros and strings can have an unlimited number of arguments.
706 .BI \[rs]? anything \[rs]?
707 When used in a diversion, this will transparently embed
711 is read in copy mode.
713 When the diversion is reread,
717 may not contain newlines; use
719 if you want to embed newlines in a diversion.
723 is also recognised in copy mode and turned into a single internal
724 code; it is this code that terminates
736 .Text \[rs]?\[rs]\[rs]?\[rs]\[rs]\[rs]\[rs]?\[rs]\[rs]\[rs]\[rs]\[rs]\[rs]\[rs]\c
737 .Text \[rs]nx\[rs]\[rs]\[rs]\[rs]?\[rs]\[rs]?\[rs]?
759 This increases the width of the preceding character so that the
760 spacing between that character and the following character will be
761 correct if the following character is a roman character.
764 . nop For example, if an italic f is immediately followed by a roman
765 . nop right parenthesis, then in many fonts the top right portion of
766 . nop the f will overlap the top left of the right parenthesis
767 . nop producing \f[I]f\f[R])\f[R], which is ugly.
771 . ie \n(.g \f[I]f\/\f[R])\f[R]
772 . el \f[I]f\|\f[R])\f[R]
773 . nop and avoids this problem.
775 It is a good idea to use this escape sequence whenever an italic
776 character is immediately followed by a roman character without any
781 This modifies the spacing of the following character so that the
782 spacing between that character and the preceding character will
783 correct if the preceding character is a roman character.
786 . nop For example, inserting
788 . nop between the parenthesis and the f changes
789 . nop \f[R](\f[I]f\f[R] to
790 . ie \n(.g \f[R](\,\f[I]f\f[R].
791 . el \f[R](\^\f[I]f\f[R].
793 It is a good idea to use this escape sequence whenever a roman
794 character is immediately followed by an italic character without any
801 except that it behaves like a character declared with the
803 request to be transparent for the purposes of end-of-sentence
808 This produces an unbreakable space that stretches like a normal
809 inter-word space when a line is adjusted.
813 This causes the insertion of a zero-width break point.
817 within a word but without insertion of a soft hyphen character.
821 Everything up to and including the next newline is ignored.
823 This is interpreted in copy mode.
829 does not ignore the terminating newline.
832 .\" --------------------------------------------------------------------
834 .\" --------------------------------------------------------------------
840 for number register object named
842 The new name and the old name will be exactly equivalent.
846 is undefined, a warning of type
848 will be generated, and the request will be ignored.
854 for request, string, macro, or diversion object named
857 The new name and the old name will be exactly equivalent (it is
858 similar to a hard rather than a soft link).
862 is undefined, a warning of type
864 will be generated, and the request will be ignored.
874 requests only create a new object if the name of the macro, diversion
875 or string diversion is currently undefined or if it is defined to be a
876 request; normally they modify the value of an existing object.
880 Append to macro indirectly.
884 request below for more information.
890 but compatibility mode is switched off during execution.
892 To be more precise, a `compatibility save' token is inserted at the
893 beginning of the macro addition, and a `compatibility restore' token at
896 As a consequence, the requests
902 can be intermixed freely since the compatibility save/\:restore tokens
903 only affect the macro parts defined by
910 This request `unformats' the diversion
914 and space characters (and some escape sequences) that were formatted
917 will be treated like ordinary input characters when
920 Useful for diversions in conjunction with the
924 It can be also used for gross hacks; for example, this
944 will set register\~\c
948 Note that glyph information (font, font size, etc.) is not preserved;
957 but compatibility mode is switched off during expansion.
959 To be more precise, a `compatibility save' token is inserted at the
960 beginning of the string, and a `compatibility restore' token at the end.
962 As a consequence, the requests
968 can be intermixed freely since the compatibility save/\:restore tokens
969 only affect the (sub)strings defined by
976 Print a backtrace of the input stack on stderr.
980 Set the blank line macro to
982 If there is a blank line macro, it will be invoked when a blank line
983 is encountered instead of the usual troff behaviour.
989 These requests are similar to the
993 requests with the exception that a partially filled line will not
994 become part of the diversion (i.e., the diversion always starts with a
995 new line) but restored after ending the diversion, discarding the
996 partially filled line which possibly comes from the diversion.
1000 Break out of a while loop.
1008 Be sure not to confuse this with the
1018 .BI .cflags\ n\ c1\ c2\|.\|.\|.\&
1022 have properties determined by
1024 which is ORed from the following:
1028 The character ends sentences (initially characters
1030 have this property).
1033 Lines can be broken before the character (initially no characters have
1034 this property); a line will not be broken at a character with this
1035 property unless the characters on each side both have non-zero
1039 Lines can be broken after the character (initially characters
1040 .B \-\[rs](hy\[rs](em
1041 have this property); a line will not be broken at a character with
1042 this property unless the characters on each side both have non-zero
1046 The character overlaps horizontally (initially characters
1047 .B \[rs](ul\[rs](rn\[rs](ru
1048 have this property).
1051 The character overlaps vertically (initially character
1056 An end-of-sentence character followed by any number of characters with
1057 this property will be treated as the end of a sentence if followed by
1058 a newline or two spaces; in other words the character is transparent
1059 for the purposes of end-of-sentence recognition; this is the same as
1060 having a zero space factor in \*[tx] (initially characters
1061 .B \[dq]')]*\[rs](dg\[rs](rq
1062 have this property).
1066 .BI .char\ c\ string
1071 Every time character
1073 needs to be printed,
1075 will be processed in a temporary environment and the result will be
1076 wrapped up into a single object.
1078 Compatibility mode will be turned off and the escape character will be
1085 Any emboldening, constant spacing or track kerning will be applied to
1086 this object rather than to individual characters in
1090 A character defined by this request can be used just like a normal
1091 character provided by the output device.
1093 In particular other characters can be translated to it with the
1095 request; it can be made the leader character by the
1097 request; repeated patterns can be drawn with the character using the
1101 escape sequences; words containing the character can be hyphenated
1104 request is used to give the character a hyphenation code.
1107 There is a special anti-recursion feature: use of character within the
1108 character's definition will be handled like normal characters not
1112 A character definition can be removed with the
1118 Chop the last character off macro, string, or diversion
1120 This is useful for removing the newline from the end of diversions
1121 that are to be interpolated as strings.
1125 Close the stream named
1128 will no longer be an acceptable argument to the
1138 Finish the current iteration of a while loop.
1150 is non-zero or missing, enable colors (this is the default), otherwise
1157 is non-zero or missing, enable compatibility mode, otherwise disable
1160 In compatibility mode, long names are not recognised, and the
1161 incompatibilities caused by long names do not arise.
1164 .BI .defcolor\ xxx\ scheme\ color_components
1167 can be one of the following values:
1173 (four components), and
1179 Color components can be given either as a hexadecimal string or as
1180 positive decimal integers in the range 0-65535.
1182 A hexadecimal string contains all color components concatenated; it
1183 must start with either
1187 The former specifies hex values in the range 0-255 (which are
1188 internally multiplied by\~257), the latter in the range 0-65535.
1190 Examples: #FFC0CB (pink), ##ffff0000ffff (magenta).
1192 A new scaling indicator\~\c
1194 has been introduced which multiplies its value by\~65536; this makes
1195 it convenient to specify color components as fractions in the range 0
1203 .Text .defcolor darkgreen rgb 0.1f 0.5f 0.2f
1211 is the default scaling indicator for the
1213 request, thus the above statement is equivalent to
1218 .Text .defcolor darkgreen rgb 0.1 0.5 0.2
1226 (which is device-specific) can't be redefined.
1228 It is possible that the default color for
1236 Define macro indirectly.
1238 The following example
1267 but compatibility mode is switched off during execution.
1269 On entry, the current compatibility mode is saved and restored at exit.
1275 with compatibility mode disabled.
1288 would have the same effect as
1297 except that it would work even if compatibility mode had been enabled.
1299 Note that the previous compatibility mode is restored before any files
1310 but compatibility mode is switched off during expansion.
1312 To be more precise, a `compatibility save' token is inserted at the
1313 beginning of the string, and a `compatibility restore' token at the end.
1317 Save current escape character.
1321 Restore escape character saved with
1323 Without a previous call to
1326 will be the new escape character.
1330 Copy the contents of environment
1332 to the current environment.
1334 No pushing or popping of environments will be done.
1338 Set the current font family to
1340 The current font family is part of the current environment.
1343 is missing, switch back to previous font family.
1345 The value at start-up is `T'.
1347 See the description of the
1349 request for more information on font families.
1352 .BI .fchar\ c\ string
1353 Define fallback character
1357 The syntax of this request is the same as the
1359 request; the only difference is that a character defined with
1361 hides the glyph with the same name in the current font, whereas a
1362 character defined with
1364 is checked only if the particular glyph isn't found in the current font.
1366 This test happens before checking special fonts.
1369 .BI .fspecial\ f\ s1\ s2\|.\|.\|.\&
1370 When the current font is
1375 will be special, that is, they will searched for characters not in
1378 Any fonts specified in the
1380 request will be searched after fonts specified in the
1390 Whenever a font named
1392 is referred to in an
1394 escape sequence, or in the
1410 is missing, or equal to
1414 will not be translated.
1417 .BI .hcode \ c1\ code1\ c2\ code2\|.\|.\|.\&
1418 Set the hyphenation code of character
1426 A hyphenation code must be a single input character (not a special
1427 character) other than a digit or a space.
1429 Initially each lower-case letter \%a-z has a hyphenation code, which is
1430 itself, and each upper-case letter \%A-Z has a hyphenation code which is
1431 the lower-case version of itself.
1439 Set the current hyphenation language to
1441 Hyphenation exceptions specified with the
1443 request and hyphenation patterns specified with the
1445 request are both associated with the current hyphenation language.
1449 request is usually invoked by the
1455 Set the maximum number of consecutive hyphenated lines to\~\c
1459 is negative, there is no maximum.
1461 The default value is\~\-1.
1463 This value is associated with the current environment.
1465 Only lines output from an environment count towards the maximum
1466 associated with that environment.
1468 Hyphens resulting from
1470 are counted; explicit hyphens are not.
1474 Read hyphenation patterns from
1476 this will be searched for in the same way that
1478 is searched for when the
1480 option is specified.
1482 It should have the same format as (simple) \*[tx] patterns files.
1484 More specifically, the following scanning rules are implemented.
1488 A percent sign starts a comment (up to the end of the line) even if
1489 preceded by a backslash.
1492 No support for `digraphs' like
1500 (character code of\~\c
1502 in the range 0-127) are recognized; other use of
1511 checks for the expression
1512 .B \[rs]patterns{.\|.\|.}
1513 (possibly with whitespace before and after the braces).
1515 Everything between the braces is taken as hyphenation patterns.
1521 are not allowed in patterns.
1525 .B \[rs]hyphenation{.\|.\|.}
1526 gives a list of hyphenation exceptions.
1533 For backwards compatibility, if
1535 is missing, the whole file is treated as a list of hyphenation patterns
1536 (only recognizing the
1538 character as the start of a comment).
1544 request to map the encoding used in hyphenation patterns files to
1548 The set of hyphenation patterns is associated with the current language
1555 request is usually invoked by the
1557 file; a second call replaces the old patterns with the new ones.
1563 except that the hyphenation patterns from
1565 are appended to the patterns already loaded in the current language.
1568 .BI .hpfcode\ a\ b\ c\ d\ .\|.\|.
1569 After reading a hyphenation patterns file with the
1573 request, convert all characters with character code\~\c
1575 in the recently read patterns to character code\~\c
1583 Initially, all character codes map to themselves.
1587 must be integers in the range 0 to\~255.
1589 Note that it is even possible to use character codes which are invalid in
1596 .I hyphenation margin
1599 when the current adjustment mode is not\~\c
1601 the line will not be hyphenated if the line is no more than
1605 The default hyphenation margin is\~0.
1607 The default scaling indicator for this request is\~\c
1609 The hyphenation margin is associated with the current environment.
1611 The current hyphenation margin is available in the
1618 .I hyphenation space
1621 when the current adjustment mode is\~\c
1623 don't hyphenate the line if the line can be justified by adding no
1626 extra space to each word space.
1628 The default hyphenation space is\~0.
1630 The default scaling indicator for this request is\~\c
1632 The hyphenation space is associated with the current environment.
1634 The current hyphenation space is available in the
1642 for which a line interrupted with
1644 counts as one input line.
1650 is non-zero or missing, enable pairwise kerning, otherwise disable it.
1653 .BI .length\ xx\ string
1654 Compute the length of
1656 and return it in the number register
1658 (which is not necessarily defined before).
1664 is non-zero or missing, enable line-tabs mode, otherwise disable it
1665 (which is the default).
1667 In line-tabs mode, tab distances are computed relative to the
1668 (current) output line.
1670 Otherwise they are taken relative to the input line.
1672 For example, the following
1679 .Text .ds x a\[rs]t\[rs]c
1680 .Text .ds y b\[rs]t\[rs]c
1699 In line-tabs mode, the same code gives
1707 Line-tabs mode is associated with the current environment; the
1708 read-only number register
1709 .B \\[rs]n[.linetabs]
1710 is set to\~1 if in line-tabs mode, and 0 otherwise.
1718 is searched for in the same directories as macro files for the the
1720 command line option.
1722 If the file name to be included has the form
1728 instead and vice versa.
1734 This is similar to `.if\ 1'.
1740 built-in condition true and the
1742 built-in condition false.
1744 This can be reversed using the
1749 .BI .open\ stream\ filename
1752 for writing and associate the stream named
1763 .BI .opena\ stream\ filename
1768 exists, append to it instead of truncating it.
1774 directly to the intermediate output (subject to copy-mode interpretation);
1777 used at the top level.
1779 An initial double quote in
1781 is stripped off to allow initial blanks.
1785 Print the names and contents of all currently defined number registers
1789 .BI .psbb \ filename
1790 Get the bounding box of a PostScript image
1792 This file must conform to Adobe's Document Structuring Conventions;
1793 the command looks for a
1795 comment to extract the bounding box values.
1797 After a successful call, the coordinates (in PostScript units) of the
1798 lower left and upper right corner can be found in the registers
1806 If some error has occurred, the four registers are set to zero.
1810 This behaves like the
1812 request except that input comes from the standard output of
1817 Print the names and positions of all traps (not including input line
1818 traps and diversion traps) on stderr.
1820 Empty slots in the page trap list are printed as well, because they
1821 can affect the priority of subsequently planted traps.
1825 Set the post-vertical line space to
1827 default scale indicator is\~\c
1830 This value will be added to each line after it has been output.
1832 With no argument, the post-vertical line space is set to its previous
1836 The total vertical line spacing consists of four components:
1840 with a negative value which are applied before the line is output, and
1844 with a positive value which are applied after the line is output.
1847 .BI .rchar\ c1\ c2\|.\|.\|.\&
1848 Remove the definitions of characters
1851 This undoes the effect of a
1857 Within a macro, return immediately.
1859 No effect otherwise.
1865 Right justify the next
1869 Without an argument right justify the next input line.
1871 The number of lines to be right justified is available in the
1875 This implicitly does
1879 request implicitly does
1884 Rename number register
1891 Set the soft hyphen character to
1895 is omitted, the soft hyphen character will be set to the default
1897 The soft hyphen character is the character which will be inserted when
1898 a word is hyphenated at a line break.
1900 If the soft hyphen character does not exist in the font of the
1901 character immediately preceding a potential break point, then the line
1902 will not be broken at that point.
1904 Neither definitions (specified with the
1906 request) nor translations (specified with the
1908 request) are considered when finding the soft hyphen character.
1912 In a macro, shift the arguments by
1914 positions: argument\~\c
1920 will no longer be available.
1924 is missing, arguments will be shifted by\~1.
1926 Shifting by negative amounts is currently undefined.
1929 .BI .sizes\ s1\ s2\|.\|.\|.\|sn\ [0]
1930 This command is similar to the
1936 It sets the available font sizes for the current font to
1938 .IR s2 ,\|.\|.\|.\|,\~ sn
1941 The list of sizes can be terminated by an optional\~\c
1946 can also be a range of sizes
1949 Contrary to the font file command, the list can't extend over more
1953 .BI .special\ s1\ s2\|.\|.\|.\&
1957 are special and will be searched for characters not in the current
1961 .BI .spreadwarn\ limit
1964 emit a warning if the additional space inserted for each space between
1965 words in an output line is larger or equal to
1968 A negative value is changed to zero; no argument toggles the warning on
1969 and off without changing
1972 The default scaling indicator is\~\c
1982 .B .spreadwarn\ 0.2m
1983 will cause a warning if
1985 must add 0.2m or more for each interword space in a line.
1987 This request is active only if text is justified to both margins (using
1994 with font position\~\c
1996 A font position can be associated either with a font or with a style.
1998 The current font is the index of a font position and so is also either
2001 When it is a style, the font that is actually used is the font the
2002 name of which is the concatenation of the name of the current family
2003 and the name of the current style.
2005 For example, if the current font is\~1 and font position\~1 is
2006 associated with style\~\c
2008 and the current font family is\~\c
2014 If the current font is not a style, then the current family is ignored.
2023 are applied to a style, then they will instead be applied to the
2024 member of the current family corresponding to that style.
2026 The default family can be set with the
2034 file controls which font positions (if any) are initially associated
2035 with styles rather than fonts.
2038 .BI .substring\ xx\ n1\ [ n2 ]
2039 Replace the string named
2041 with the substring defined by the indices
2045 The first character in the string has index\~0.
2049 is omitted, it is taken to be equal to the string's length.
2055 is negative, it will be counted from the end of the string,
2058 The last character has index\~-1, the character before the last
2059 character has index\~-2, etc.
2062 .BI .tkf\ f\ s1\ n1\ s2\ n2
2063 Enable track kerning for font
2065 When the current font is
2067 the width of every character will be increased by an amount between
2071 when the current point size is less than or equal to
2073 the width will be increased by
2075 when it is greater than or equal to
2077 the width will be increased by
2079 when the point size is greater than or equal to
2081 and less than or equal to
2083 the increase in width is a linear function of the point size.
2091 is read in copy mode and written on the standard error, but an initial
2094 is stripped off to allow initial blanks.
2100 but without writing a final newline.
2104 Transparently output the contents of file
2106 Each line is output as if preceded by
2108 however, the lines are not subject to copy-mode interpretation.
2110 If the file does not end with a newline, then a newline will be added.
2112 For example, you can define a macro\~\c
2114 containing the contents of file\~\c
2133 request, the file cannot contain characters such as
2135 that are not legal troff input characters.
2139 This is the same as the
2141 request except that the
2143 request will use the character code (if any) before the character
2176 This is the same as the
2178 request except that the translations do not apply to text that is
2179 transparently throughput into a diversion with
2211 built-in condition false, and the
2213 built-in condition true.
2215 This undoes the effect of the
2221 This request `unformats' the diversion
2225 request, which tries to convert formatted elements of the diversion
2226 back to input tokens as much as possible,
2228 will only handle tabs and spaces between words (usually caused by
2229 spaces or newlines in the input) specially.
2231 The former are treated as if they were input tokens, and the latter
2232 are stretchable again.
2234 Note that the vertical size of lines is not preserved.
2236 Glyph information (font, font size, space width, etc.) is retained.
2238 Useful in conjunction with the
2246 Enable vertical position traps if
2248 is non-zero, disable them otherwise.
2250 Vertical position traps are traps set by the
2258 request are not vertical position traps.
2260 The parameter that controls whether vertical position traps are
2263 Initially vertical position traps are enabled.
2269 is the sum of the numbers associated with each warning that is to be
2270 enabled; all other warnings will be disabled.
2272 The number associated with each warning is listed in
2273 .BR @g@troff (@MAN1EXT@).
2277 will disable all warnings, and
2279 will disable all warnings except that about missing characters.
2283 is not given, all warnings will be enabled.
2287 Set the scaling indicator used in warnings to
2300 At startup, it is set to\~\c
2304 .BI .while \ c\ anything
2311 can be any condition acceptable to an
2315 can comprise multiple lines if the first line starts with
2317 and the last line ends with
2326 .BI .write\ stream\ anything
2332 must previously have been the subject of an
2336 is read in copy mode;
2342 .BI .writec\ stream\ anything
2345 but without writing a final newline.
2348 .BI .writem\ stream\ xx
2349 Write the contents of the macro or string
2354 must previously have been the subject of an
2358 is read in copy mode.
2361 .\" --------------------------------------------------------------------
2362 .SS "Extended requests"
2363 .\" --------------------------------------------------------------------
2367 When used in a diversion, this will embed in the diversion an object
2368 which, when reread, will cause the contents of
2370 to be transparently copied through to the output.
2372 In UNIX troff, the contents of
2374 is immediately copied through to the output regardless of whether
2375 there is a current diversion; this behaviour is so anomalous that it
2376 must be considered a bug.
2382 is not a number, this will switch to a named environment called
2384 The environment should be popped with a matching
2386 request without any arguments, just as for numbered environments.
2388 There is no limit on the number of named environments; they will be
2389 created the first time that they are referenced.
2393 When two arguments are given to the
2395 request, the second argument gives the
2396 .IR "sentence space size" .
2397 If the second argument is not given, the sentence space size
2398 will be the same as the word space size.
2400 Like the word space size, the sentence space is in units of
2401 one twelfth of the spacewidth parameter for the current font.
2403 Initially both the word space size and the sentence
2406 Contrary to UNIX troff, GNU troff handles this request in nroff mode
2407 also; a given value is then rounded down to the nearest multiple
2410 The sentence space size is used in two circumstances.
2412 If the end of a sentence occurs at the end of a line in fill mode,
2413 then both an inter-word space and a sentence space will be added; if
2414 two spaces follow the end of a sentence in the middle of a line, then
2415 the second space will be a sentence space.
2417 Note that the behaviour of UNIX troff will be exactly that exhibited
2418 by GNU troff if a second argument is never given to the
2422 In GNU troff, as in UNIX troff, you should always follow a sentence
2423 with either a newline or two spaces.
2426 .BI .ta\ n1\ n2\|.\|.\|.nn \ T\ r1\ r2\|.\|.\|.\|rn
2427 Set tabs at positions
2429 .IR n2 ,\|.\|.\|.\|,
2431 and then set tabs at
2433 .IR nn + r2 ,\|.\|.\|.\|,
2437 .IR nn + rn + r2 ,\|.\|.\|.\|,
2450 will set tabs every half an inch.
2454 .\" --------------------------------------------------------------------
2455 .SS "New number registers"
2456 .\" --------------------------------------------------------------------
2458 The following read-only registers are available:
2462 1\~if compatibility mode is in effect, 0\~otherwise.
2466 The depth of the last character added to the current environment.
2468 It is positive if the character extends below the baseline.
2472 The number of lines remaining to be centered, as set by the
2478 The height of the last character added to the current environment.
2480 It is positive if the character extends above the baseline.
2484 1\~if colors are enabled, 0\~otherwise.
2488 The skew of the last character added to the current environment.
2492 of a character is how far to the right of the center of a character
2493 the center of an accent over that character should be placed.
2497 The name or number of the current environment.
2499 This is a string-valued register.
2503 The current font family.
2505 This is a string-valued register.
2509 The current (internal) real font name.
2511 This is a string-valued register.
2513 If the current font is a style, the value of
2515 is the proper concatenation of family and style name.
2519 The number of the next free font position.
2525 Macros should use this to determine whether they are running under GNU
2530 The current hyphenation language as set by the
2536 The number of immediately preceding consecutive hyphenated lines.
2540 The maximum allowed number of consecutive hyphenated lines, as set by
2547 The current hyphenation flags (as set by the
2553 The current hyphenation margin (as set by the
2559 The current hyphenation space (as set by the
2565 The indent that applies to the current output line.
2569 Set to a positive value if last output line is interrupted (i.e., if
2575 1\~if pairwise kerning is enabled, 0\~otherwise.
2579 The current ligature mode (as set by the
2584 .B \[rs]n[.linetabs]
2585 The current line-tabs mode (as set by the
2591 The line length that applies to the current output line.
2595 The title length as set by the
2601 The amount of space that was needed in the last
2603 request that caused a trap to be sprung.
2605 Useful in conjunction with the
2611 1\~if no-space mode is active, 0\~otherwise.
2615 The number of the next page, either the value set by a
2617 request, or the number of the current page plus\~1.
2621 The current pointsize in scaled points.
2625 The last-requested pointsize in scaled points.
2629 The current post-vertical line space as set with the
2635 The number of lines to be right-justified as set by the
2641 The last requested pointsize in points as a decimal fraction.
2643 This is a string-valued register.
2649 These give the values of the parameters set by the first and second
2656 A string representation of the current tab settings suitable for use
2657 as an argument to the
2663 The amount of vertical space truncated by the most recently sprung
2664 vertical position trap, or, if the trap was sprung by a
2666 request, minus the amount of vertical motion produced by the
2670 In other words, at the point a trap is sprung, it represents the
2671 difference of what the vertical position would have been but for the
2672 trap, and what the vertical position actually is.
2674 Useful in conjunction with the
2680 1\~if vertical position traps are enabled, 0\~otherwise.
2684 The sum of the numbers associated with each of the currently enabled
2687 The number associated with each warning is listed in
2688 .BR @g@troff (@MAN1EXT@).
2692 The major version number.
2694 For example, if the version number is 1.03, then
2700 The minor version number.
2702 For example, if the version number is 1.03, then
2708 The revision number of groff.
2718 These four registers are set by the
2720 request and contain the bounding box values (in PostScript units) of a
2721 given PostScript image.
2724 The following read/write registers are set by the
2736 registers, but take account of the heights and depths of characters.
2740 The amount of horizontal space (possibly negative) that should be
2741 added to the last character before a subscript.
2745 How far to right of the center of the last character in the
2747 argument, the center of an accent from a roman font should be placed
2748 over that character.
2751 Other available read/write number registers are:
2755 The current input line number.
2757 is a read-only alias to this register.
2761 The number of hours past midnight.
2763 Initialized at start-up.
2767 The current horizontal position at input line.
2771 The number of minutes after the hour.
2773 Initialized at start-up.
2777 The number of seconds after the minute.
2779 Initialized at start-up.
2783 The return value of the system() function executed by the last
2789 If greater than\~0, the maximum number of objects on the input stack.
2791 If less than or equal to\~0, there is no limit on the number of
2792 objects on the input stack.
2794 With no limit, recursion can continue until virtual memory is
2801 Note that the traditional
2805 is the current year minus 1900.
2808 .\" --------------------------------------------------------------------
2810 .\" --------------------------------------------------------------------
2813 predefines a single (read/write) string-based register,
2815 which contains the argument given to the
2817 command line option, namely the current output device (for example,
2821 Note that this is not the same as the (read-only) number register
2823 which is defined to be\~1 if
2827 command line option, and zero otherwise.
2829 This behaviour is different to UNIX troff.
2832 Fonts not listed in the
2834 file are automatically mounted on the next available font position
2835 when they are referenced.
2837 If a font is to be mounted explicitly with the
2839 request on an unused font position, it should be mounted on the first
2840 unused font position, which can be found in the
2844 does not enforce this strictly, it will not allow a font to be mounted
2845 at a position whose number is much greater than that of any currently
2849 Interpolating a string does not hide existing macro arguments.
2851 Thus in a macro, a more efficient way of doing
2854 .BI . xx\ \[rs]\[rs]$@
2859 .BI \[rs]\[rs]*[ xx ]\[rs]\[rs]
2862 If the font description file contains pairwise kerning information,
2863 characters from that font will be kerned.
2865 Kerning between two characters can be inhibited by placing a
2870 In a string comparison in a condition, characters that appear at
2871 different input levels to the first delimiter character will not be
2872 recognised as the second or third delimiters.
2874 This applies also to the
2880 escape sequence, a character that appears at a different input level
2881 to the starting delimiter character will not be recognised as the
2882 closing delimiter character.
2884 The same is true for
2896 When decoding a macro or string argument that is delimited by double
2897 quotes, a character that appears at a different input level to the starting
2898 delimiter character will not be recognised as the closing delimiter
2901 The implementation of
2903 ensures that the double quotes surrounding an argument will appear the
2904 same input level, which will be different to the input level of the
2907 In a long escape name
2909 will not be recognized as a closing delimiter except when it occurs at
2910 the same input level as the opening
2913 In compatibility mode, no attention is paid to the input-level.
2916 There are some new types of condition:
2920 True if there is a number register named
2925 True if there is a string, macro, diversion, or request named
2930 True if there is a color named
2935 True if there is a character
2941 character or a special character
2944 .BI \[rs][ xxx ]\f[R];
2945 the condition will also be true if
2947 has been defined by the
2954 request can now map characters onto
2958 It is now possible to have whitespace between the first and second dot
2959 (or the name of the ending macro) to end a macro definition.
2968 .Text . nop Hello, I'm `foo'.
2969 .Text . nop I will now define `bar'.
2971 .Text . nop Hello, I'm `bar'.
2980 .\" --------------------------------------------------------------------
2981 .SH "INTERMEDIATE OUTPUT FORMAT"
2982 .\" --------------------------------------------------------------------
2984 This section describes the format output by GNU troff.
2986 The output format used by GNU troff is very similar to that used
2987 by Unix device-independent troff.
2989 Only the differences are documented here.
2992 .\" --------------------------------------------------------------------
2994 .\" --------------------------------------------------------------------
2998 command is in scaled points (units of
3002 is the argument to the
3004 command in the DESC file).
3008 command is also in scaled points.
3011 .\" --------------------------------------------------------------------
3013 .\" --------------------------------------------------------------------
3017 Print character with index\~\c
3019 (a non-negative integer) of the current font.
3024 line is present in the DESC file, troff will use the following two
3030 is any sequence of characters terminated by a space or a newline; the
3031 first character should be printed at the current position, the current
3032 horizontal position should be increased by the width of the first
3033 character, and so on for each character.
3035 The width of the character is that given in the font file,
3036 appropriately scaled for the current point size, and rounded so that
3037 it is a multiple of the horizontal resolution.
3039 Special characters cannot be printed using this command.
3045 command except that after printing each character, the current
3046 horizontal position is increased by the sum of the width of that
3051 Note that single characters can have the eighth bit set, as can the
3052 names of fonts and special characters.
3055 The names of characters and fonts can be of arbitrary length; drivers
3056 should not assume that they will be only two characters long.
3059 When a character is to be printed, that character will always be
3060 in the current font.
3062 Unlike device-independent troff, it is not necessary for drivers to
3063 search special fonts to find a character.
3066 For color support, some new commands have been added:
3069 .Text \f[B]mc \f[I]cyan magenta yellow\f[R]
3073 .Text \f[B]mg \f[I]gray\f[R]
3075 .Text \f[B]mk \f[I]cyan magenta yellow black\f[R]
3077 .Text \f[B]mr \f[I]red green blue\f[R]
3078 Set the color components of the current drawing color, using various
3082 resets the drawing color to the default value.
3084 The arguments are integers in the range 0 to 65536.
3089 device control command has been extended.
3092 .Text \f[B]x u \f[I]n\f[R]
3095 is\~1, start underlining of spaces.
3099 is\~0, stop underlining of spaces.
3101 This is needed for the
3103 request in nroff mode and is ignored otherwise.
3106 .\" --------------------------------------------------------------------
3107 .SS "Drawing Commands"
3108 .\" --------------------------------------------------------------------
3112 drawing command has been extended.
3114 These extensions will not be used by GNU pic if the
3119 .Text \f[B]Df \f[I]n\f[R]\*[ic]\[rs]n
3120 Set the shade of gray to be used for filling solid objects to
3123 must be an integer between 0 and 1000, where 0 corresponds solid white
3124 and 1000 to solid black, and values in between correspond to
3125 intermediate shades of gray.
3127 This applies only to solid circles, solid ellipses and solid
3130 By default, a level of 1000 will be used.
3132 Whatever color a solid object has, it should completely obscure
3133 everything beneath it.
3135 A value greater than 1000 or less than 0 can also be used: this means
3136 fill with the shade of gray that is currently being used for lines and
3139 Normally this will be black, but some drivers may provide a way of
3143 .Text \f[B]DC \f[I]d\f[R]\*[ic]\[rs]n
3144 Draw a solid circle with a diameter of
3146 with the leftmost point at the current position.
3149 .Text \f[B]DE \f[I]dx dy\f[R]\*[ic]\[rs]n
3150 Draw a solid ellipse with a horizontal diameter of
3152 and a vertical diameter of
3154 with the leftmost point at the current position.
3160 .Text \f[B]Dp\f[R] $dx sub 1$ $dy sub 1$ $dx sub 2$ $dy sub 2$ $...$ $dx sub n$ $dy sub n$\[rs]n
3161 Draw a polygon with, for $i = 1 ,..., n+1$, the
3163 vertex at the current position
3165 $+ sum from j=1 to i-1 ( dx sub j , dy sub j )$.
3167 At the moment, GNU pic only uses this command to generate triangles
3171 .Text \f[B]DP\f[R] $dx sub 1$ $dy sub 1$ $dx sub 2$ $dy sub 2$ $...$ $dx sub n$ $dy sub n$\[rs]n
3175 but draw a solid rather than outlined polygon.
3178 .Text \f[B]Dt \f[I]n\f[R]\*[ic]\[rs]n
3179 Set the current line thickness to
3183 Traditionally Unix troff drivers use a line thickness proportional to
3184 the current point size; drivers should continue to do this if no
3186 command has been given, or if a
3188 command has been given with a negative value of
3192 selects the smallest available line thickness.
3195 A difficulty arises in how the current position should be changed after
3196 the execution of these commands.
3198 This is not of great importance since the code generated by GNU pic
3199 does not depend on this.
3201 Given a drawing command of the form
3203 \f[B]\[rs]D\[fm]\f[I]c\f[R] $x sub 1$ $y sub 1$ $x sub 2$ $y sub 2$ $...$ $x sub n$ $y sub n$\[fm]
3215 Unix troff will treat each of the $x sub i$ as a horizontal quantity,
3216 and each of the $y sub i$ as a vertical quantity and will assume that
3217 the width of the drawn object is $sum from i=1 to n x sub i$,
3218 and that the height is $sum from i=1 to n y sub i$.
3220 (The assumption about the height can be seen by examining the
3224 registers after using such a
3226 command in a \[rs]w escape sequence).
3228 This rule also holds for all the original drawing commands with the
3231 For the sake of compatibility GNU troff also follows this rule, even
3232 though it produces an ugly result in the case of the
3234 and, to a lesser extent,
3238 Thus after executing a
3242 \f[B]D\f[I]c\f[R] $x sub 1$ $y sub 1$ $x sub 2$ $y sub 2$ $...$ \c
3243 $x sub n$ $y sub n$\[rs]n
3246 the current position should be increased by
3248 $( sum from i=1 to n x sub i , sum from i=1 to n y sub i )$.
3251 Another set of extensions is
3254 .Text \f[B]DFc \f[I]cyan magenta yellow\f[R]\*[ic]\[rs]n
3256 .Text \f[B]DFd\f[R]\*[ic]\[rs]n
3258 .Text \f[B]DFg \f[I]gray\f[R]\*[ic]\[rs]n
3260 .Text \f[B]DFk \f[I]cyan magenta yellow black\f[R]\*[ic]\[rs]n
3262 .Text \f[B]DFr \f[I]red green blue\f[R]\*[ic]\[rs]n
3263 Set the color components of the filling color similar to the
3272 The current position isn't changed by those colour commands.
3275 .\" --------------------------------------------------------------------
3276 .SS "Device Control Commands"
3277 .\" --------------------------------------------------------------------
3279 There is a continuation convention which permits the argument to the
3281 command to contain newlines: when outputting the argument to the
3283 command, GNU troff will follow each newline in the argument with a
3285 character (as usual, it will terminate the entire argument with a
3286 newline); thus if the line after the line containing the
3290 then the newline ending the line containing the
3292 command should be treated as part of the argument to the
3296 should be ignored, and the part of the line following the
3298 should be treated like the part of the line following the
3303 The first three output commands are guaranteed to be:
3312 .\" --------------------------------------------------------------------
3313 .SH INCOMPATIBILITIES
3314 .\" --------------------------------------------------------------------
3316 In spite of the many extensions, groff has retained compatibility to
3317 classical troff to a large degree.
3319 For the cases where the extensions lead to collisions, a special
3320 compatibility mode with the restricted, old functionality was created
3324 .\" --------------------------------------------------------------------
3325 .SS "Groff Language"
3326 .\" --------------------------------------------------------------------
3330 .B compatibility mode
3331 that allows to process roff code written for classical
3333 or for other implementations of roff in a consistent way.
3336 Compatibility mode can be turned on with the
3338 command line option, and turned on or off with the
3344 is\~1 if compatibility mode is on, 0\~otherwise.
3347 This became necessary because the GNU concept for long names causes
3348 some incompatibilities.
3355 as defining a string
3361 mode, this will be considered as a call of a macro named
3371 as references to a string or number register called
3375 takes this as the start of a long name.
3379 .IR "compatibility mode" ,
3380 groff interprets these things in the traditional way; so long
3381 names are not recognized.
3384 On the other hand, groff in
3386 does not allow to use the single-character escapes
3415 (character c) in names of strings, macros, diversions, number
3416 registers, fonts or environments, whereas
3423 escape sequence can be helpful in avoiding these escape sequences in
3427 Fractional pointsizes cause one noteworthy incompatibility.
3434 request ignores scale indicators and so
3441 will set the pointsize to 10\~points, whereas in groff native mode the
3442 pointsize will be set to 10\~scaled points.
3447 mode, there is a fundamental difference between unformatted input
3448 characters, and formatted output characters.
3450 Everything that affects how an output character will be output is
3451 stored with the character; once an output character has been
3452 constructed it is unaffected by any subsequent requests that are
3453 executed, including the
3463 Normally output characters are constructed from input characters at
3464 the moment immediately before the character is added to the current
3467 Macros, diversions and strings are all, in fact, the same type of
3468 object; they contain lists of input characters and output characters
3472 An output character does not behave like an input character for the
3473 purposes of macro processing; it does not inherit any of the special
3474 properties that the input character from which it was constructed
3477 The following example will make things clearer.
3484 .Text \[rs]\[rs]\[rs]\[rs]
3495 this will be printed as
3497 So each pair of input backslashes
3499 is turned into a single output backslash
3501 and the resulting output backslashes are not interpreted as escape
3502 characters when they are reread.
3506 would interpret them as escape characters when they were reread and
3507 would end up printing a single backslash
3511 In GNU, the correct way to get a printable version of the backslash
3516 escape sequence, but classical troff does not provide a clean feature
3517 for getting a non-syntactical backslash.
3519 A close method is the printable version of the current escape
3522 escape sequence; this works if the current escape character is not
3525 It works in both GNU mode and compatibility mode, while dirty tricks
3526 like specifying a sequence of multiple backslashes do not work
3527 reliably; for the different handling in diversions, macro definitions,
3528 or text mode quickly leads to a confusion about the necessary number of
3532 To store an escape sequence in a diversion that will be interpreted
3533 when the diversion is reread, either the traditional
3535 transparent output facility or the
3538 escape sequence can be used.
3541 .\" --------------------------------------------------------------------
3542 .SS "Intermediate Output"
3543 .\" --------------------------------------------------------------------
3545 The groff intermediate output format is in a state of evolution.
3547 So far it has some incompatibilities, but it is intended to establish
3548 a full compatibility to the classical troff output format.
3550 Actually the following incompatibilities exist:
3553 The positioning after the drawing of the polygons conflicts with the
3554 classical definition.
3557 The intermediate output cannot be rescaled to other devices as
3558 classical "device-independent" troff did.
3561 .\" --------------------------------------------------------------------
3563 .\" --------------------------------------------------------------------
3565 Copyright (C) 1989, 2001, 2002 Free Software Foundation, Inc.
3568 This document is distributed under the terms of the FDL (GNU Free
3569 Documentation License) version 1.1 or later.
3571 You should have received a copy of the FDL on your system, it is also
3572 available on-line at the
3573 .URL http://\:www.gnu.org/\:copyleft/\:fdl.html "GNU copyleft site" .
3575 This document was written by James Clark, with modifications by
3576 .MTO wl@gnu.org "Werner Lemberg"
3578 .MTO bwarken@mayn.de "Bernd Warken" .
3581 This document is part of
3583 the GNU roff distribution.
3585 Formerly, the contents of this document was kept in the manual
3587 .BR @g@troff (@MAN1EXT@).
3588 Only the parts dealing with the language aspects of the different
3590 systems were carried over into this document.
3594 command line options and warnings are still documented in
3595 .BR @g@troff (@MAN1EXT@).
3597 .\" --------------------------------------------------------------------
3599 .\" --------------------------------------------------------------------
3606 presents all groff documentation within a single document.
3609 .BR groff (@MAN1EXT@)
3610 A list of all documentation around
3614 .BR groff (@MAN7EXT@)
3615 A description of the
3617 language, including a short, but complete reference of all predefined
3618 requests, registers, and escapes of plain
3620 From the command line, this is called using
3623 .ShellCommand man\~7\~groff
3626 .BR roff (@MAN7EXT@)
3629 systems, including pointers to further historical documentation.
3634 .I Nroff/\:Troff User's Manual
3637 of 1976 in the revision of
3640 .URL http://\:cm.bell-labs.com/\:cm/\:cs/\:cstr/\:54.ps.gz \
3641 "classical troff documentation" .
3644 .\" --------------------------------------------------------------------
3646 .\" --------------------------------------------------------------------
3648 .\" Local Variables:
projects / dragonfly.git / blob