This file is indexed.

/usr/share/doc/racket/reference/threadgroups.html is in racket-doc 6.1-4.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"/><title>14.8&nbsp;Thread Groups</title><link rel="stylesheet" type="text/css" href="../scribble.css" title="default"/><link rel="stylesheet" type="text/css" href="extras.css" title="default"/><link rel="stylesheet" type="text/css" href="../racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-style.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../doc-site.css" title="default"/><script type="text/javascript" src="../scribble-common.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../doc-site.js"></script><script type="text/javascript" src="../local-redirect/local-redirect.js"></script><script type="text/javascript" src="../local-redirect/local-user-redirect.js"></script><!--[if IE 6]><style type="text/css">.SIEHidden { overflow: hidden; }</style><![endif]--></head><body id="doc-racket-lang-org"><div class="tocset"><div class="tocview"><div class="tocviewlist tocviewlisttopspace"><div class="tocviewtitle"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,&quot;tocview_0&quot;);">&#9658;</a></td><td></td><td><a href="index.html" class="tocviewlink" data-pltdoc="x"><span style="font-weight: bold">The Racket Reference</span></a></td></tr></table></div><div class="tocviewsublisttop" style="display: none;" id="tocview_0"><table cellspacing="0" cellpadding="0"><tr><td align="right">1&nbsp;</td><td><a href="model.html" class="tocviewlink" data-pltdoc="x">Language Model</a></td></tr><tr><td align="right">2&nbsp;</td><td><a href="notation.html" class="tocviewlink" data-pltdoc="x">Notation for Documentation</a></td></tr><tr><td align="right">3&nbsp;</td><td><a href="syntax.html" class="tocviewlink" data-pltdoc="x">Syntactic Forms</a></td></tr><tr><td align="right">4&nbsp;</td><td><a href="data.html" class="tocviewlink" data-pltdoc="x">Datatypes</a></td></tr><tr><td align="right">5&nbsp;</td><td><a href="structures.html" class="tocviewlink" data-pltdoc="x">Structures</a></td></tr><tr><td align="right">6&nbsp;</td><td><a href="mzlib_class.html" class="tocviewlink" data-pltdoc="x">Classes and Objects</a></td></tr><tr><td align="right">7&nbsp;</td><td><a href="mzlib_unit.html" class="tocviewlink" data-pltdoc="x">Units</a></td></tr><tr><td align="right">8&nbsp;</td><td><a href="contracts.html" class="tocviewlink" data-pltdoc="x">Contracts</a></td></tr><tr><td align="right">9&nbsp;</td><td><a href="match.html" class="tocviewlink" data-pltdoc="x">Pattern Matching</a></td></tr><tr><td align="right">10&nbsp;</td><td><a href="control.html" class="tocviewlink" data-pltdoc="x">Control Flow</a></td></tr><tr><td align="right">11&nbsp;</td><td><a href="concurrency.html" class="tocviewlink" data-pltdoc="x">Concurrency and Parallelism</a></td></tr><tr><td align="right">12&nbsp;</td><td><a href="Macros.html" class="tocviewlink" data-pltdoc="x">Macros</a></td></tr><tr><td align="right">13&nbsp;</td><td><a href="input-and-output.html" class="tocviewlink" data-pltdoc="x">Input and Output</a></td></tr><tr><td align="right">14&nbsp;</td><td><a href="security.html" class="tocviewselflink" data-pltdoc="x">Reflection and Security</a></td></tr><tr><td align="right">15&nbsp;</td><td><a href="os.html" class="tocviewlink" data-pltdoc="x">Operating System</a></td></tr><tr><td align="right">16&nbsp;</td><td><a href="memory.html" class="tocviewlink" data-pltdoc="x">Memory Management</a></td></tr><tr><td align="right">17&nbsp;</td><td><a href="unsafe.html" class="tocviewlink" data-pltdoc="x">Unsafe Operations</a></td></tr><tr><td align="right">18&nbsp;</td><td><a href="running.html" class="tocviewlink" data-pltdoc="x">Running Racket</a></td></tr><tr><td align="right"></td><td><a href="doc-bibliography.html" class="tocviewlink" data-pltdoc="x">Bibliography</a></td></tr><tr><td align="right"></td><td><a href="doc-index.html" class="tocviewlink" data-pltdoc="x">Index</a></td></tr></table></div></div><div class="tocviewlist"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,&quot;tocview_1&quot;);">&#9660;</a></td><td>14&nbsp;</td><td><a href="security.html" class="tocviewlink" data-pltdoc="x">Reflection and Security</a></td></tr></table><div class="tocviewsublistbottom" style="display: block;" id="tocview_1"><table cellspacing="0" cellpadding="0"><tr><td align="right">14.1&nbsp;</td><td><a href="Namespaces.html" class="tocviewlink" data-pltdoc="x">Namespaces</a></td></tr><tr><td align="right">14.2&nbsp;</td><td><a href="eval.html" class="tocviewlink" data-pltdoc="x">Evaluation and Compilation</a></td></tr><tr><td align="right">14.3&nbsp;</td><td><a href="load-lang.html" class="tocviewlink" data-pltdoc="x">The <span class="RktModLink"><span class="RktSym">racket/<span class="mywbr"> &nbsp;</span>load</span></span> Language</a></td></tr><tr><td align="right">14.4&nbsp;</td><td><a href="Module_Names_and_Loading.html" class="tocviewlink" data-pltdoc="x">Module Names and Loading</a></td></tr><tr><td align="right">14.5&nbsp;</td><td><a href="chaperones.html" class="tocviewlink" data-pltdoc="x">Impersonators and Chaperones</a></td></tr><tr><td align="right">14.6&nbsp;</td><td><a href="securityguards.html" class="tocviewlink" data-pltdoc="x">Security Guards</a></td></tr><tr><td align="right">14.7&nbsp;</td><td><a href="custodians.html" class="tocviewlink" data-pltdoc="x">Custodians</a></td></tr><tr><td align="right">14.8&nbsp;</td><td><a href="" class="tocviewselflink" data-pltdoc="x">Thread Groups</a></td></tr><tr><td align="right">14.9&nbsp;</td><td><a href="inspectors.html" class="tocviewlink" data-pltdoc="x">Structure Inspectors</a></td></tr><tr><td align="right">14.10&nbsp;</td><td><a href="modprotect.html" class="tocviewlink" data-pltdoc="x">Code Inspectors</a></td></tr><tr><td align="right">14.11&nbsp;</td><td><a href="plumbers.html" class="tocviewlink" data-pltdoc="x">Plumbers</a></td></tr><tr><td align="right">14.12&nbsp;</td><td><a href="Sandboxed_Evaluation.html" class="tocviewlink" data-pltdoc="x">Sandboxed Evaluation</a></td></tr></table></div></div></div><div class="tocsub"><div class="tocsubtitle">On this page:</div><table class="tocsublist" cellspacing="0"><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._make-thread-group%29%29" class="tocsublink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>thread-<wbr></wbr>group</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._thread-group~3f%29%29" class="tocsublink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">thread-<wbr></wbr>group?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._current-thread-group%29%29" class="tocsublink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">current-<wbr></wbr>thread-<wbr></wbr>group</span></span></a></td></tr></table></div></div><div class="maincolumn"><div class="main"><div class="navsettop"><span class="navleft"><form class="searchform"><input class="searchbox" style="color: #888;" type="text" value="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, &quot;6.1&quot;, &quot;../&quot;);" onfocus="this.style.color=&quot;black&quot;; this.style.textAlign=&quot;left&quot;; if (this.value == &quot;...search manuals...&quot;) this.value=&quot;&quot;;" onblur="if (this.value.match(/^ *$/)) { this.style.color=&quot;#888&quot;; this.style.textAlign=&quot;center&quot;; this.value=&quot;...search manuals...&quot;; }"/></form>&nbsp;&nbsp;<a href="../index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot(&quot;6.1&quot;);">top</a></span><span class="navright">&nbsp;&nbsp;<a href="custodians.html" title="backward to &quot;14.7 Custodians&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="security.html" title="up to &quot;14 Reflection and Security&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="inspectors.html" title="forward to &quot;14.9 Structure Inspectors&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div><h4 x-source-module="(lib &quot;scribblings/reference/reference.scrbl&quot;)" x-part-tag="&quot;threadgroups&quot;">14.8<tt>&nbsp;</tt><a name="(part._threadgroups)"></a>Thread Groups</h4><p>A <a name="(tech._thread._group)"></a><span style="font-style: italic">thread group</span> is a collection of threads and other thread
groups that have equal claim to the CPU. By nesting thread groups and
by creating certain threads within certain groups, a programmer can
control the amount of CPU allocated to a set of threads. Every thread
belongs to a thread group, which is determined by the
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._current-thread-group%29%29" class="RktValLink" data-pltdoc="x">current-thread-group</a></span> parameter when the thread is
created. Thread groups and custodians (see <a href="custodians.html" data-pltdoc="x">Custodians</a>)
are independent.</p><p>The root thread group receives all of the CPU that the operating
system gives Racket. Every thread or nested group in a particular
thread group receives equal allocation of the CPU (a portion of the
group&rsquo;s access), although a thread may relinquish part of its
allocation by sleeping or synchronizing with other processes.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._make-thread-group))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-thread-group%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-thread-group</a></span></span><span class="hspace">&nbsp;</span>[<span class="RktVar">group</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._thread-group~3f%29%29" class="RktValLink" data-pltdoc="x">thread-group?</a></span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">group</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._thread-group~3f%29%29" class="RktValLink" data-pltdoc="x">thread-group?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._current-thread-group%29%29" class="RktValLink" data-pltdoc="x">current-thread-group</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Creates a new thread group that belongs to <span class="RktVar">group</span>.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._thread-group~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._thread-group~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">thread-group?</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">v</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> is a thread group value, <span class="RktVal">#f</span>
otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>parameter</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._current-thread-group))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._current-thread-group%29%29" class="RktValDef RktValLink" data-pltdoc="x">current-thread-group</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._thread-group~3f%29%29" class="RktValLink" data-pltdoc="x">thread-group?</a></span></p></blockquote></td></tr><tr><td><span class="RktPn">(</span><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._current-thread-group%29%29" class="RktValDef RktValLink" data-pltdoc="x">current-thread-group</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">group</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">group</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._thread-group~3f%29%29" class="RktValLink" data-pltdoc="x">thread-group?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">A <a href="eval-model.html#%28tech._parameter%29" class="techoutside" data-pltdoc="x"><span class="techinside">parameter</span></a> that determines the thread group for newly created
threads.</div></p><div class="navsetbottom"><span class="navleft"><form class="searchform"><input class="searchbox" style="color: #888;" type="text" value="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, &quot;6.1&quot;, &quot;../&quot;);" onfocus="this.style.color=&quot;black&quot;; this.style.textAlign=&quot;left&quot;; if (this.value == &quot;...search manuals...&quot;) this.value=&quot;&quot;;" onblur="if (this.value.match(/^ *$/)) { this.style.color=&quot;#888&quot;; this.style.textAlign=&quot;center&quot;; this.value=&quot;...search manuals...&quot;; }"/></form>&nbsp;&nbsp;<a href="../index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot(&quot;6.1&quot;);">top</a></span><span class="navright">&nbsp;&nbsp;<a href="custodians.html" title="backward to &quot;14.7 Custodians&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="security.html" title="up to &quot;14 Reflection and Security&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="inspectors.html" title="forward to &quot;14.9 Structure Inspectors&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div></div></div><div id="contextindicator">&nbsp;</div></body></html>