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diff --git a/doc/groff.html.node/Manipulating-Filling-and-Adjustment.html b/doc/groff.html.node/Manipulating-Filling-and-Adjustment.html new file mode 100644 index 0000000..632aade --- /dev/null +++ b/doc/groff.html.node/Manipulating-Filling-and-Adjustment.html @@ -0,0 +1,501 @@ +<!DOCTYPE html> +<html> +<!-- Created by GNU Texinfo 7.0.3, https://www.gnu.org/software/texinfo/ --> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> +<!-- This manual documents GNU troff version 1.23.0. + +Copyright © 1994-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A +copy of the license is included in the section entitled "GNU Free +Documentation License". --> +<title>Manipulating Filling and Adjustment (The GNU Troff Manual)</title> + +<meta name="description" content="Manipulating Filling and Adjustment (The GNU Troff Manual)"> +<meta name="keywords" content="Manipulating Filling and Adjustment (The GNU Troff Manual)"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta name="viewport" content="width=device-width,initial-scale=1"> + +<link href="index.html" rel="start" title="Top"> +<link href="Request-Index.html" rel="index" title="Request Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="GNU-troff-Reference.html" rel="up" title="GNU troff Reference"> +<link href="Manipulating-Hyphenation.html" rel="next" title="Manipulating Hyphenation"> +<link href="Registers.html" rel="prev" title="Registers"> +<style type="text/css"> +<!-- +a.copiable-link {visibility: hidden; text-decoration: none; line-height: 0em} +div.example {margin-left: 3.2em} +span.r {font-family: initial; font-weight: normal; font-style: normal} +span:hover a.copiable-link {visibility: visible} +strong.def-name {font-family: monospace; font-weight: bold; font-size: larger} +--> +</style> + + +</head> + +<body lang="en"> +<div class="section-level-extent" id="Manipulating-Filling-and-Adjustment"> +<div class="nav-panel"> +<p> +Next: <a href="Manipulating-Hyphenation.html" accesskey="n" rel="next">Manipulating Hyphenation</a>, Previous: <a href="Registers.html" accesskey="p" rel="prev">Registers</a>, Up: <a href="GNU-troff-Reference.html" accesskey="u" rel="up">GNU <code class="code">troff</code> Reference</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Request-Index.html" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<h3 class="section" id="Manipulating-Filling-and-Adjustment-1">5.9 Manipulating Filling and Adjustment</h3> +<a class="index-entry-id" id="index-manipulating-filling-and-adjustment"></a> +<a class="index-entry-id" id="index-filling-and-adjustment_002c-manipulating"></a> +<a class="index-entry-id" id="index-adjustment-and-filling_002c-manipulating"></a> +<a class="index-entry-id" id="index-justifying-text"></a> +<a class="index-entry-id" id="index-text_002c-justifying"></a> + +<a class="index-entry-id" id="index-break-1"></a> +<a class="index-entry-id" id="index-line-break"></a> +<a class="index-entry-id" id="index-bp-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-ce-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-cf-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-fi-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-fl-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-in-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-nf-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-rj-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-sp-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-ti-request_002c-causing-implicit-break"></a> +<a class="index-entry-id" id="index-trf-request_002c-causing-implicit-break"></a> +<p>When an output line is pending (see below), a break moves the drawing +position to the beginning of the next text baseline, interrupting +filling. Various ways of causing breaks were shown in <a class="ref" href="Breaking.html">Breaking</a>. +The <code class="code">br</code> request likewise causes a break. Several other requests +imply breaks: <code class="code">bp</code>, <code class="code">ce</code>, <code class="code">cf</code>, <code class="code">fi</code>, <code class="code">fl</code>, +<code class="code">in</code>, <code class="code">nf</code>, <code class="code">rj</code>, <code class="code">sp</code>, <code class="code">ti</code>, and <code class="code">trf</code>. +If the no-break control character is used with any of these requests, +GNU <code class="code">troff</code> suppresses the break; instead the requested operation +takes effect at the next break. ‘<samp class="samp">'br</samp>’ does nothing. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 55n +This line is normally filled and adjusted. +.br +A line's alignment is decided +'ce \" Center the next input line (no break). +when it is output. +This line returns to normal filling and adjustment. + ⇒ This line is normally filled and adjusted. + ⇒ A line's alignment is decided when it is output. + ⇒ This line returns to normal filling and adjustment. +</pre></div></div> + +<a class="index-entry-id" id="index-pending-output-line"></a> +<a class="index-entry-id" id="index-partially-collected-line"></a> +<a class="index-entry-id" id="index-output-line-properties"></a> +<a class="index-entry-id" id="index-properties-of-output-lines"></a> +<p>Output line properties like page offset, indentation, adjustment, and +even the location of its text baseline, are not determined until the +line has been broken. An output line is said to be <em class="dfn">pending</em> if +some input has been collected but an output line corresponding to it has +not yet been written; such an output line is also termed <em class="dfn">partially +collected</em>. If no output line is pending, it is as if a break has +already happened; additional breaks, whether explicit or implicit, have +no effect. If the vertical drawing position is negative—as it is when +the formatter starts up—a break starts a new page (even if no output +line is pending) unless an end-of-input macro is being interpreted. +See <a class="xref" href="End_002dof_002dinput-Traps.html">End-of-input Traps</a>. +</p> +<dl class="first-deffn"> +<dt class="deffn" id="index-_002ebr"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.br</code></strong><a class="copiable-link" href='#index-_002ebr'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-br"></a> +<p>Break the line: emit any pending output line without adjustment. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">foo bar +.br +baz +'br +qux + ⇒ foo bar + ⇒ baz qux +</pre></div></div> +</dd></dl> + +<p>Sometimes you want to prevent a break within a phrase or between a +quantity and its units. +</p> +<dl class="first-deffn"> +<dt class="deffn" id="index-_005c_007e-1"><span class="category-def">Escape sequence: </span><span><strong class="def-name"><code class="t">\~</code><span class="r"><i class="slanted"></i></span><code class="t"></code></strong><a class="copiable-link" href='#index-_005c_007e-1'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_005c_007e"></a> +<a class="index-entry-id" id="index-unbreakable-space-_0028_005c_007e_0029"></a> +<a class="index-entry-id" id="index-space_002c-unbreakable-_0028_005c_007e_0029"></a> +<p>Insert an unbreakable space that is adjustable like an ordinary space. +It is discarded from the end of an output line if a break is forced. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">Set the output speed to\~1. +There are 1,024\~bytes in 1\~KiB. +J.\~F.\~Ossanna wrote the original CSTR\~#54. +</pre></div></div> +</dd></dl> + +<p>By default, GNU <code class="code">troff</code> fills text and adjusts it to reach the +output line length. The <code class="code">nf</code> request disables filling; the +<code class="code">fi</code> request reënables it. +</p> +<dl class="first-deffn"> +<dt class="deffn" id="index-_002efi"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.fi</code></strong><a class="copiable-link" href='#index-_002efi'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-fi"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002eu_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.u]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002eu_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002eu"></a> +<a class="index-entry-id" id="index-filling-of-output_002c-enabling-_0028fi_0029"></a> +<a class="index-entry-id" id="index-output_002c-filling_002c-enablement-of-_0028fi_0029"></a> +<a class="index-entry-id" id="index-fill-mode-_0028fi_0029_002c-enabling"></a> +<a class="index-entry-id" id="index-mode_002c-fill-_0028fi_0029_002c-enabling"></a> +<p>Enable filling of output lines; a pending output line is broken. The +read-only register <code class="code">.u</code> is set to 1. The filling enablement +status, sometimes called <em class="dfn">fill mode</em>, is associated with the +environment (see <a class="pxref" href="Environments.html">Environments</a>). See <a class="xref" href="Line-Continuation.html">Line Continuation</a>, for +interaction with the <code class="code">\c</code> escape sequence. +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002enf"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.nf</code></strong><a class="copiable-link" href='#index-_002enf'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-nf"></a> +<a class="index-entry-id" id="index-filling-of-output_002c-disabling-_0028nf_0029"></a> +<a class="index-entry-id" id="index-output_002c-filling_002c-disablement-of-_0028nf_0029"></a> +<a class="index-entry-id" id="index-no_002dfill-mode"></a> +<a class="index-entry-id" id="index-mode_002c-no_002dfill"></a> +<a class="index-entry-id" id="index-fill-mode_002c-disabling"></a> +<a class="index-entry-id" id="index-mode_002c-fill_002c-disabling"></a> +<p>Disable filling of output lines: the output line length (see <a class="pxref" href="Line-Layout.html">Line Layout</a>) is ignored and output lines are broken where the input lines +are. A pending output line is broken and adjustment is suppressed. The +read-only register <code class="code">.u</code> is set to 0. The filling enablement +status is associated with the environment (see <a class="pxref" href="Environments.html">Environments</a>). See +<a class="ref" href="Line-Continuation.html">Line Continuation</a>, for interaction with the <code class="code">\c</code> escape +sequence. +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002ead"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.ad</code></strong> <var class="def-var-arguments">[<span class="r"><i class="slanted">mode</i></span>]</var><a class="copiable-link" href='#index-_002ead'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-ad"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002ej_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.j]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002ej_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002ej"></a> +<p>Enable output line adjustment in <var class="var">mode</var>, taking effect when the +pending (or next) output line is broken. Adjustment is suppressed when +filling is. <var class="var">mode</var> can have one of the following values. +</p> +<dl class="table"> +<dt><code class="code">b</code></dt> +<dt><code class="code">n</code></dt> +<dd><p>Adjust “normally”: if the output line does not consume the distance +between the indentation and the configured output line length, GNU +<code class="code">troff</code> stretches adjustable spaces within the line until that +length is reached. When the indentation is zero, this mode spreads the +line to both the left and right margins. This is the GNU <code class="code">troff</code> +default. +</p> +</dd> +<dt id='index-centered-text-_0028filled_0029'><span><code class="code">c</code><a class="copiable-link" href='#index-centered-text-_0028filled_0029'> ¶</a></span></dt> +<dd><p>Center filled text. Contrast with the <code class="code">ce</code> request, which centers +text <em class="emph">without</em> filling it. +</p> +</dd> +<dt id='index-ragged_002dright-text'><span><code class="code">l</code><a class="copiable-link" href='#index-ragged_002dright-text'> ¶</a></span></dt> +<dd><p>Align text to the left without adjusting it. +</p> +</dd> +<dt id='index-ragged_002dleft-text'><span><code class="code">r</code><a class="copiable-link" href='#index-ragged_002dleft-text'> ¶</a></span></dt> +<dd><p>Align text to the right without adjusting it. +</p></dd> +</dl> + +<p><var class="var">mode</var> can also be a value previously stored in the <code class="code">.j</code> +register. Using <code class="code">ad</code> without an argument is the same as ‘<samp class="samp">.ad +\n[.j]</samp>’; unless filling is disabled, GNU <code class="code">troff</code> resumes adjusting +lines in the same way it did before adjustment was disabled by +invocation of the <code class="code">na</code> request. +</p> +<a class="index-entry-id" id="index-adjustment-mode-register-_0028_002ej_0029"></a> +<p>The adjustment mode and enablement status are encoded in the read-only +register <code class="code">.j</code>. These parameters are associated with the +environment (see <a class="pxref" href="Environments.html">Environments</a>). +</p> +<p>The value of <code class="code">.j</code> for any adjustment mode is an implementation +detail and should not be relied upon as a programmer’s interface. Do +not write logic to interpret or perform arithmetic on it. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 48n +.de AD +. br +. ad \\$1 +.. +.de NA +. br +. na +.. +left +.AD r +.nr ad \n(.j +right +.AD c +center +.NA +left +.AD +center +.AD \n(ad +right +</pre></div></div> +<div class="example"> +<div class="group"><pre class="example-preformatted"> ⇒ left + ⇒ right + ⇒ center + ⇒ left + ⇒ center + ⇒ right +</pre></div></div> +</dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002ena"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.na</code></strong><a class="copiable-link" href='#index-_002ena'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-na"></a> +<p>Disable output line adjustment. This produces the same output as +left-alignment, but the value of the adjustment mode register <code class="code">.j</code> +is altered differently. The adjustment mode and enablement status are +associated with the environment (see <a class="pxref" href="Environments.html">Environments</a>). +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002ebrp"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.brp</code></strong><a class="copiable-link" href='#index-_002ebrp'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-brp"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cp-1"><span class="category-def">Escape sequence: </span><span><strong class="def-name"><code class="t">\p</code><span class="r"><i class="slanted"></i></span><code class="t"></code></strong><a class="copiable-link" href='#index-_005cp-1'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_005cp"></a> +<p>Break, adjusting the line per the current adjustment mode. <code class="code">\p</code> +schedules a break with adjustment at the next word boundary. The escape +sequence is itself neither a break nor a space of any kind; it can thus +be placed in the middle of a word to cause a break at the end of that +word. +</p> +<p>Breaking with immediate adjustment can produce ugly results since GNU +<code class="code">troff</code> doesn’t have a sophisticated paragraph-building algorithm, +as TeX has, for example. Instead, GNU <code class="code">troff</code> fills and adjusts +a paragraph line by line. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 4.5i +This is an uninteresting sentence. +This is an uninteresting sentence.\p +This is an uninteresting sentence. +</pre></div></div> + +<p>is formatted as follows. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">This is an uninteresting sentence. This is +an uninteresting sentence. +This is an uninteresting sentence. +</pre></div></div> +</dd></dl> + +<a class="index-entry-id" id="index-productive-input-line"></a> +<a class="index-entry-id" id="index-input-line_002c-productive"></a> +<a class="index-entry-id" id="index-line_002c-productive-input"></a> +<p>To clearly present the next couple of requests, we must introduce the +concept of “productive” input lines. A <em class="dfn">productive input line</em> is +one that directly produces formatted output. Text lines produce +output,<a class="footnote" id="DOCF53" href="groff.html_fot.html#FOOT53"><sup>53</sup></a> as do control +lines containing requests like <code class="code">tl</code> or escape sequences like +<code class="code">\D</code>. Macro calls are not <em class="emph">directly</em> productive, and thus not +counted, but their interpolated contents can be. Empty requests, and +requests and escape sequences that define registers or strings or alter +the formatting environment (as with changes to the size, face, height, +slant, or color of the type) are not productive. We will also preview +the output line continuation escape sequence, <code class="code">\c</code>, which +“connects” two input lines that would otherwise be counted separately. +<a class="footnote" id="DOCF54" href="groff.html_fot.html#FOOT54"><sup>54</sup></a> +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.de hello +Hello, world! +.. +.ce \" center output of next productive input line +. +.nr junk-reg 1 +.ft I +Chorus: \c +.ft +.hello +Went the day well? + ⇒ <i class="slanted">Chorus:</i> Hello, world! + ⇒ Went the day well? +</pre></div></div> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002ece"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.ce</code></strong> <var class="def-var-arguments">[<span class="r"><i class="slanted">n</i></span>]</var><a class="copiable-link" href='#index-_002ece'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-ce"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002ece_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.ce]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002ece_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002ece-1"></a> +<a class="index-entry-id" id="index-centered-text-_0028unfilled_0029"></a> +<a class="index-entry-id" id="index-centering-lines-_0028ce_0029"></a> +<a class="index-entry-id" id="index-lines_002c-centering-_0028ce_0029"></a> +<p>Break (unless the no-break control character is used), center the output +of the next <var class="var">n</var> productive input lines with respect to the line +length and indentation without filling, then break again regardless of +the invoking control character. +If the argument is not positive, centering is disabled. Omitting the +argument implies an <var class="var">n</var> of ‘<samp class="samp">1</samp>’. The count of lines remaining +to be centered is stored in the read-only register <code class="code">.ce</code> and is +associated with the environment (see <a class="pxref" href="Environments.html">Environments</a>). +</p> +<a class="index-entry-id" id="index-ce-request_002c-difference-from-_002ead-c"></a> +<p>While the ‘<samp class="samp">.ad c</samp>’<!-- /@w --> request also centers text, it fills the text +as well. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.de FR +This is a small text fragment that shows the differences +between the `.ce' and the `.ad c' requests. +.. +.ll 4i +.ce 1000 +.FR +.ce 0 + +.ad c +.FR + ⇒ This is a small text fragment that shows + ⇒ the differences + ⇒ between the ‘.ce’ and the ‘.ad c’ requests. + ⇒ + ⇒ This is a small text fragment that shows + ⇒ the differences between the ‘.ce’ and + ⇒ the ‘.ad c’ requests. +</pre></div></div> + +<p>The previous example illustrates a common idiom of turning centering on +for a quantity of lines far in excess of what is required, and off again +after the text to be centered. This technique relieves humans of +counting lines for requests that take a count of input lines as an +argument. +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002erj"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.rj</code></strong> <var class="def-var-arguments">[<span class="r"><i class="slanted">n</i></span>]</var><a class="copiable-link" href='#index-_002erj'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-rj"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002erj_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.rj]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002erj_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002erj-1"></a> +<a class="index-entry-id" id="index-justifying-text-_0028rj_0029"></a> +<a class="index-entry-id" id="index-text_002c-justifying-_0028rj_0029"></a> +<a class="index-entry-id" id="index-right_002djustifying-_0028rj_0029"></a> +<p>Break (unless the no-break control character is used), align the output +of the next <var class="var">n</var> productive input lines to the right margin without +filling, then break again regardless of the control character. +If the argument is not positive, right-alignment is disabled. Omitting +the argument implies an <var class="var">n</var> of ‘<samp class="samp">1</samp>’. The count of lines +remaining to be right-aligned is stored in the read-only register +<code class="code">.rj</code> and is associated with the environment +(see <a class="pxref" href="Environments.html">Environments</a>). +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 49n +.rj 3 +At first I hoped that such a technically unsound +project would collapse but I soon realized it was +doomed to success. \[em] C. A. R. Hoare + ⇒ At first I hoped that such a technically unsound + ⇒ project would collapse but I soon realized it was + ⇒ doomed to success. -- C. A. R. Hoare +</pre></div></div> +</dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002ess"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.ss</code></strong> <var class="def-var-arguments">word-space-size [<span class="r"><i class="slanted">additional-sentence-space-size</i></span>]</var><a class="copiable-link" href='#index-_002ess'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-ss"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002ess_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.ss]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002ess_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002ess-1"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002esss_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.sss]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002esss_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002esss"></a> +<a class="index-entry-id" id="index-word-space-size-register-_0028_002ess_0029"></a> +<a class="index-entry-id" id="index-size-of-word-space-register-_0028_002ess_0029"></a> +<a class="index-entry-id" id="index-space-between-words-register-_0028_002ess_0029"></a> +<a class="index-entry-id" id="index-inter_002dsentence-space-size-register-_0028_002esss_0029"></a> +<a class="index-entry-id" id="index-sentence-space-size-register-_0028_002esss_0029"></a> +<a class="index-entry-id" id="index-size-of-sentence-space-register-_0028_002esss_0029"></a> +<a class="index-entry-id" id="index-space-between-sentences-register-_0028_002esss_0029"></a> +<p>Set the sizes of spaces between words and +sentences<a class="footnote" id="DOCF55" href="groff.html_fot.html#FOOT55"><sup>55</sup></a> in twelfths +of font’s space width (typically one-fourth to one-third em for Western +scripts). The default for both parameters is 12. Negative values +are erroneous. +<a class="index-entry-id" id="index-inter_002dword-spacing_002c-minimal"></a> +<a class="index-entry-id" id="index-minimal-inter_002dword-spacing"></a> +<a class="index-entry-id" id="index-space_002c-between-words"></a> +The first argument is a minimum; if an output line undergoes adjustment, +such spaces may increase in width. +<a class="index-entry-id" id="index-inter_002dsentence-space_002c-additional"></a> +<a class="index-entry-id" id="index-additional-inter_002dsentence-space"></a> +<a class="index-entry-id" id="index-space_002c-between-sentences"></a> +The optional second argument sets the amount of additional space +separating sentences on the same output line. If omitted, this amount +is set to <var class="var">word-space-size</var>. The request is ignored if there are no +parameters. +</p> +<a class="index-entry-id" id="index-filling_002c-and-inter_002dsentence-space"></a> +<a class="index-entry-id" id="index-mode_002c-fill_002c-and-inter_002dsentence-space"></a> +<p>Additional inter-sentence space is used only if the output line is not +full when the end of a sentence occurs in the input. If a sentence ends +at the end of an input line, then both an inter-word space and an +inter-sentence space are added to the output; if two spaces follow the +end of a sentence in the middle of an input line, then the second space +becomes an inter-sentence space in the output. Additional +inter-sentence space is not adjusted, but the inter-word space that +always precedes it may be. Further input spaces after the second, if +present, are adjusted as normal. +</p> +<p>The read-only registers <code class="code">.ss</code> and <code class="code">.sss</code> hold the minimal +inter-word space and additional inter-sentence space amounts, +respectively. These parameters are part of the environment +(see <a class="pxref" href="Environments.html">Environments</a>), and rounded down to the nearest multiple +of 12 on terminals. +</p> +<a class="index-entry-id" id="index-discardable-horizontal-space"></a> +<a class="index-entry-id" id="index-space_002c-discardable_002c-horizontal"></a> +<a class="index-entry-id" id="index-horizontal-discardable-space"></a> +<p>The <code class="code">ss</code> request can insert discardable horizontal space; that is, +space that is discarded at a break. For example, some footnote styles +collect the notes into a single paragraph with large gaps between +each note. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 48n +1.\~J. Fict. Ch. Soc. 6 (2020), 3\[en]14. +.ss 12 48 \" applies to next sentence ending +Reprints no longer available through FCS. +.ss 12 \" go back to normal +2.\~Better known for other work. + ⇒ 1. J. Fict. Ch. Soc. 6 (2020), 3-14. Reprints + ⇒ no longer available through FCS. 2. Better + ⇒ known for other work. +</pre></div></div> + +<p>If <em class="emph">undiscardable</em> space is required, use the <code class="code">\h</code> escape +sequence. +</p></dd></dl> + + + +</div> +<hr> +<div class="nav-panel"> +<p> +Next: <a href="Manipulating-Hyphenation.html">Manipulating Hyphenation</a>, Previous: <a href="Registers.html">Registers</a>, Up: <a href="GNU-troff-Reference.html">GNU <code class="code">troff</code> Reference</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Request-Index.html" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |