<!DOCTYPE html>
<html class="client-nojs vector-feature-night-mode-disabled vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-sticky-header-enabled" lang="en" dir="ltr"><head>
<meta charset="UTF-8">
<title>KeyKOS</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="canonical" href="https://en.wikipedia.org/wiki/KeyKOS"> <link href="./mw/ext.cite.styles.css" rel="stylesheet" type="text/css">
<link href="./mw/skins.vector.icons.css" rel="stylesheet" type="text/css">
<link href="./mw/skins.vector.search.codex.styles.css" rel="stylesheet" type="text/css">
<link href="./mw/skins.vector.styles.css" rel="stylesheet" type="text/css">
<link href="./mw/user.styles.css" rel="stylesheet" type="text/css">
<meta name="ResourceLoaderDynamicStyles" content="">
<link rel="stylesheet" type="text/css" href="./mw/site.styles.css">
<link rel="stylesheet" type="text/css" href="./mw/noscript.css">
<link rel="stylesheet" type="text/css" href="./footer.css">
<link rel="stylesheet" type="text/css" href="./vector-2022.css">
</head>
<body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-KeyKOS rootpage-KeyKOS skin-vector-2022 action-view">
<div class="mw-page-container">
<div class="mw-page-container-inner">
<div class="mw-content-container">
<main id="content" class="mw-body">
<header class="mw-body-header vector-page-titlebar">
<h1 id="firstHeading" class="firstHeading mw-first-heading">
<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">KeyKOS</span></span>
</h1>
</header>
<a id="top"></a>
<div id="bodyContent" class="vector-body ve-init-mw-desktopArticleTarget-targetContainer" aria-labelledby="firstHeading" data-mw-ve-target-container="">
<div id="mw-content-text" class="mw-body-content mw-content-ltr" lang="en" dir="ltr"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr">
<style data-mw-deduplicate="TemplateStyles:r1295905060">
/* start https://en.wikipedia.org/ */
.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}
/* end https://en.wikipedia.org/ */
</style><table class="infobox vevent"><tbody><tr><th colspan="2" class="infobox-above" style="background-color: #e0e0e0;">KeyKOS</th></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="Programmer" title="Programmer">Developer</a></th><td class="infobox-data"><a href="Tymshare" title="Tymshare">Tymshare</a> (Norm Hardy, Bill Frantz, Charlie Landau)<br><a href="McDonnell_Douglas" title="McDonnell Douglas">McDonnell Douglas</a><br>Key Logic</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="Programming_language" title="Programming language">Written in</a></th><td class="infobox-data"><a href="C_(programming_language)" title="C (programming language)">C</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">OS family</th><td class="infobox-data"><a href="Capability-based_security" title="Capability-based security">Capability-based</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Working state</th><td class="infobox-data">Discontinued</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">1977<span style="display:none"> (<span class="bday dtstart published updated">1977</span>)</span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="Software_release_life_cycle" title="Software release life cycle">Latest release</a></th><td class="infobox-data">Final / 1988<span style="display:none"> (<span class="bday dtstart published updated">1988</span>)</span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Marketing target</th><td class="infobox-data">Research</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Available in</th><td class="infobox-data">English</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Update method</th><td class="infobox-data">Compile from <a href="Source_code" title="Source code">source code</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Supported platforms</th><td class="infobox-data"><a href="IBM_System/370" title="IBM System/370">S/370</a> <a href="IBM_mainframe" title="IBM mainframe">mainframe</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="Kernel_(operating_system)" title="Kernel (operating system)">Kernel</a> type</th><td class="infobox-data"><a href="Microkernel" title="Microkernel">Microkernel</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="User_interface" title="User interface">Default<br>user interface</a></th><td class="infobox-data"><a href="Command-line_interface" title="Command-line interface">Command-line interface</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Preceded by</th><td class="infobox-data"><a href="GNOSIS" title="GNOSIS">GNOSIS</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Succeeded by</th><td class="infobox-data"><a href="EROS_(microkernel)" title="EROS (microkernel)">Extremely Reliable Operating System</a> (EROS), CapROS, Coyotos</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Official website</th><td class="infobox-data"><span class="url"><a rel="nofollow" class="external text" href="http://cap-lore.com/CapTheory/KK">cap-lore<wbr>.com<wbr>/CapTheory<wbr>/KK</a></span></td></tr></tbody></table>
<p><b>KeyKOS</b> is a <a href="Persistence_(computer_science)" title="Persistence (computer science)">persistent</a>, pure <a href="Capability-based_security" title="Capability-based security">capability</a>-based <a href="Capability-based_operating_system" title="Capability-based operating system">operating system</a> for the <a href="IBM" title="IBM">IBM</a> <a href="IBM_System/370" title="IBM System/370">S/370</a> <a href="IBM_mainframe" title="IBM mainframe">mainframe</a> <a href="Computer" title="Computer">computers</a>. It allows <a href="Emulator" title="Emulator">emulating</a> the environments of <a href="VM_(operating_system)" title="VM (operating system)">VM</a>, <a href="MVS" title="MVS">MVS</a>, and Portable Operating System Interface (<a href="POSIX" title="POSIX">POSIX</a>). It is a predecessor of the <a href="EROS_(microkernel)" title="EROS (microkernel)">Extremely Reliable Operating System</a> (EROS), and its successor <a href="Operating_system" title="Operating system">operating systems</a>, CapROS, and Coyotos. KeyKOS is a <a href="Nanokernel" class="mw-redirect" title="Nanokernel">nanokernel</a>-based operating system.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>
</p><p>In the mid-1970s, development of KeyKOS began at <a href="Tymshare" title="Tymshare">Tymshare</a>, Inc., under the name <a href="GNOSIS" title="GNOSIS">GNOSIS</a>. In 1984, <a href="McDonnell_Douglas" title="McDonnell Douglas">McDonnell Douglas</a> (MD) bought Tymshare. A year later MD spun off Key Logic, which bought GNOSIS and renamed it <i>KeyKOS</i>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>
<style data-mw-deduplicate="TemplateStyles:r1239543626">
/* start https://en.wikipedia.org/ */
.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}
/* end https://en.wikipedia.org/ */
</style><div class="reflist">
<div class="mw-references-wrap"><ol class="references">
<li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.cis.upenn.edu/~KeyKOS/NanoKernel/NanoKernel.html">The KeyKOS Nanokernel Architecture</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110621235229/http://www.cis.upenn.edu/~KeyKOS/NanoKernel/NanoKernel.html">Archived</a> 2011-06-21 at the <a href="Wayback_Machine" title="Wayback Machine">Wayback Machine</a></span>
</li>
<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">
/* start https://en.wikipedia.org/ */
.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("./mw/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("./mw/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("./mw/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("./mw/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}
/* end https://en.wikipedia.org/ */
</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.cap-lore.com/CapTheory/KK/EKK.html">"Roots of KeyKOS"</a>. <i>Cap-lore.com</i>.</cite></span>
</li>
</ol></div></div>
<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>
<ul><li><span class="official-website"><span class="url"><a rel="nofollow" class="external text" href="http://cap-lore.com/CapTheory/KK">Official website</a></span></span>, Norman Hardy</li>
<li><a rel="nofollow" class="external text" href="http://cap-lore.com/CapTheory/upenn/Gnosis/Gnosis.html">GNOSIS: A Prototype Operating System for the 1990s</a>, a 1979 paper, Tymshare Inc.</li>
<li><a rel="nofollow" class="external text" href="http://www.cap-lore.com/Agorics/Library/KeyKos/key370.html">KeyKOS - A Secure, High-Performance Environment for S/370</a>, a 1988 paper, Key Logic, Inc.</li></ul>
<div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">
/* start https://en.wikipedia.org/ */
.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}
/* end https://en.wikipedia.org/ */
</style><style data-mw-deduplicate="TemplateStyles:r1236075235">
/* start https://en.wikipedia.org/ */
.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}
/* end https://en.wikipedia.org/ */
</style></div><div role="navigation" class="navbox" aria-labelledby="Object-capability_security187" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><style data-mw-deduplicate="TemplateStyles:r1239400231">
/* start https://en.wikipedia.org/ */
.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}
/* end https://en.wikipedia.org/ */
</style><div id="Object-capability_security187" style="font-size:114%;margin:0 4em"><a href="Object-capability_model" title="Object-capability model">Object-capability</a> security</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="Principle_of_least_privilege" title="Principle of least privilege">Principle of least privilege</a> (PoLP)</li>
<li><a href="Confused_deputy_problem" title="Confused deputy problem">Confused deputy problem</a></li>
<li><a href="Ambient_authority" title="Ambient authority">Ambient authority</a></li>
<li><a href="File_descriptor" title="File descriptor">File descriptor</a></li>
<li><a href="C-list_(computer_security)" title="C-list (computer security)">C-list</a></li>
<li><a href="Object-capability_model" title="Object-capability model">Object-capability model</a></li>
<li><a href="Capability-based_security" title="Capability-based security">Capability-based security</a></li>
<li><a href="Capability-based_addressing" title="Capability-based addressing">Capability-based addressing</a></li>
<li><a href="Zooko's_triangle" title="Zooko's triangle">Zooko's triangle</a></li>
<li><a href="Petname" title="Petname">Petnames</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Operating_system" title="Operating system">Operating systems</a>,<br><a href="Kernel_(operating_system)" title="Kernel (operating system)">kernels</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="Capsicum_(Unix)" title="Capsicum (Unix)">Capsicum</a></li>
<li><a href="Fuchsia_(operating_system)" title="Fuchsia (operating system)">Fuchsia</a></li>
<li><a href="Genode" title="Genode">Genode</a></li>
<li><a href="GNOSIS" title="GNOSIS">GNOSIS</a> → → <a href="EROS_(microkernel)" title="EROS (microkernel)">EROS</a> → CapROS</li>
<li><a href="Hydra_(operating_system)" title="Hydra (operating system)">Hydra</a></li>
<li><a href="IMAX_432" title="IMAX 432">iMAX 432</a></li>
<li><a href="Midori_(operating_system)" title="Midori (operating system)">Midori</a></li>
<li><a href="NLTSS" title="NLTSS">NLTSS</a></li>
<li><a href="L4_microkernel_family#High_assurance:_seL4" title="L4 microkernel family">seL4</a></li>
<li><a href="HarmonyOS" title="HarmonyOS">HarmonyOS</a> (<a href="HarmonyOS_NEXT" title="HarmonyOS NEXT">HarmonyOS NEXT</a>)</li>
<li><a href="Phantom_OS" title="Phantom OS">Phantom OS</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Programming_language" title="Programming language">Programming languages</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="Caja_project" title="Caja project">Caja–Cajita</a></li>
<li><a href="E_(programming_language)" title="E (programming language)">E</a></li>
<li><a href="Joe-E" title="Joe-E">Joe-E</a></li>
<li><a href="Joule_(programming_language)" title="Joule (programming language)">Joule</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="File_system" title="File system">File systems</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="Tahoe-LAFS" title="Tahoe-LAFS">Tahoe-LAFS</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Specialised hardware</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="BiiN" title="BiiN">BiiN</a></li>
<li><a href="CAP_computer" title="CAP computer">Cambridge CAP</a></li>
<li><a href="Flex_machine" title="Flex machine">Flex</a></li>
<li><a href="IBM_System/38" title="IBM System/38">IBM System/38</a></li>
<li><a href="Intel_iAPX_432" title="Intel iAPX 432">Intel iAPX 432</a></li>
<li><a href="Plessey_System_250" title="Plessey System 250">Plessey System 250</a></li>
<li><a href="Capability_Hardware_Enhanced_RISC_Instructions" title="Capability Hardware Enhanced RISC Instructions">CHERI</a></li></ul>
</div></td></tr></tbody></table></div>
<div class="navbox-styles"></div><div role="navigation" class="navbox" aria-labelledby="Microkernels-nanokernels667" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Microkernels-nanokernels667" style="font-size:114%;margin:0 4em"><a href="Microkernel" title="Microkernel">Microkernels</a>-<a href="Microkernel#Nanokernel" title="Microkernel">nanokernels</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Kernel_(operating_system)" title="Kernel (operating system)">Kernels</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="L4_microkernel_family" title="L4 microkernel family">L4</a> family</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="Eumel" title="Eumel">Eumel</a></i> → <i><a href="L3_microkernel" class="mw-redirect" title="L3 microkernel">L3</a></i> → <a href="L4_microkernel_family" title="L4 microkernel family">L4</a>°</li>
<li><a href="Open_Kernel_Labs" title="Open Kernel Labs">OKL4</a>°</li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Macintosh" class="mw-redirect" title="Macintosh">Macintosh</a> hosted</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="Mac_OS_nanokernel" title="Mac OS nanokernel">Mac OS nanokernel</a></i></li>
<li><i><a href="NuKernel" class="mw-redirect" title="NuKernel">NuKernel</a></i></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Psion_(company)" title="Psion (company)">Psion</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="EKA1" title="EKA1">EKA1</a></i> → <i><a href="EKA2" title="EKA2">EKA2</a></i>^°</li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Amiga" title="Amiga">Amiga</a>-type</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="Exec_(Amiga)" title="Exec (Amiga)">Exec</a></i>
<ul><li><a href="Exec_(Amiga)#ExecSG" title="Exec (Amiga)">ExecSG</a></li></ul></li>
<li><a href="Quark_(kernel)" title="Quark (kernel)">Quark</a></li>
<li><i><a href="WarpOS" title="WarpOS">WarpOS</a></i></li></ul>
</div></td></tr></tbody></table><div>
<ul><li><i><a href="Adaptive_Domain_Environment_for_Operating_Systems" title="Adaptive Domain Environment for Operating Systems">ADEOS</a></i>°</li>
<li><i><a href="EROS_(microkernel)" title="EROS (microkernel)">EROS</a></i>^°</li>
<li><i><a href="K42" title="K42">K42</a></i>°</li>
<li>Little Kernel</li>
<li><i><a href="Mach_(kernel)" title="Mach (kernel)">Mach</a></i>°
<ul><li><a href="GNU_Mach" title="GNU Mach">GNU Mach</a>°</li></ul></li>
<li><i><a href="MicroEmpix" title="MicroEmpix">MicroEmpix</a></i></li>
<li><a href="Green_Hills_Software#Real-time_operating_systems" title="Green Hills Software">µ-velOSity</a>^</li>
<li><i><a href="Spring_(operating_system)#The_nucleus" title="Spring (operating system)">nucleus</a></i></li>
<li>Off++ → Plan B</li>
<li><i><a href="Taligent#Pink_system" title="Taligent">Opus</a></i></li>
<li><i><a href="PowerUP_(accelerator)#PowerUP_software" title="PowerUP (accelerator)">PowerUP</a></i></li>
<li><a href="RTLinux" title="RTLinux">RTLinux</a>°</li>
<li><a href="TI-RTOS#RTOS_kernel_overview" title="TI-RTOS">TI-RTOS kernel</a>^°</li>
<li><i><a href="Vanguard_(microkernel)" title="Vanguard (microkernel)">Vanguard</a></i></li></ul></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Operating_system" title="Operating system">Operating<br>systems</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="POSIX" title="POSIX">POSIX</a> support</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Unix-like" title="Unix-like">Unix-like</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<li><i><a href="ARX_(operating_system)" title="ARX (operating system)">ARX</a></i></li>
<li><a href="GNU_Hurd" title="GNU Hurd">GNU Hurd</a>°</li>
<li><i><a href="Lites" title="Lites">Lites</a></i></li>
<li><i><a href="Meiko_Scientific#MeikOS" title="Meiko Scientific">MeikOS</a></i></li>
<li><a href="Minix" title="Minix">Minix</a>°
<ul><li><a href="Minix-vmd" class="mw-redirect" title="Minix-vmd">Minix-vmd</a>°</li>
<li><a href="Minix_3" title="Minix 3">Minix 3</a>°</li></ul></li>
<li><i><a href="MkLinux" title="MkLinux">MkLinux</a></i>°</li>
<li><i><a href="Multi-Environment_Real-Time" title="Multi-Environment Real-Time">Multi-Environment Real-Time</a></i>^ (<i>MERT</i> – <i>Unix-RT</i>)</li>
<li><i><a href="OS2000" title="OS2000">OS2000</a></i></li>
<li><a href="QNX" title="QNX">QNX</a>^</li>
<li><a href="Redox_(operating_system)" class="mw-redirect" title="Redox (operating system)">Redox</a>°</li>
<li><i><a href="Spring_(operating_system)" title="Spring (operating system)">Spring</a></i></li>
<li><a href="Tinix" title="Tinix">Tinix</a></li>
<li><i><a href="UNICOS" title="UNICOS">UNICOS</a></i></li>
<li><i><a href="VSTa" title="VSTa">VSTa</a></i></li>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Partial</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="ChorusOS" title="ChorusOS">ChorusOS</a>^</i></li>
<li><a href="Integrity_(operating_system)" title="Integrity (operating system)">Integrity</a>^</li>
<li><a href="Nucleus_RTOS" title="Nucleus RTOS">Nucleus RTOS</a>^</li>
<li><a href="NuttX" title="NuttX">NuttX</a>^°</li>
<li><a href="Operating_System_Embedded" class="mw-redirect" title="Operating System Embedded">OSE</a>^</li>
<li><a href="RIOT_(operating_system)" title="RIOT (operating system)">RIOT</a>^°</li></ul>
</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Capability-based_security" title="Capability-based security">Capability-based</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="GNOSIS" title="GNOSIS">GNOSIS</a></i> → <i></i> → <i><a href="EROS_(microkernel)" title="EROS (microkernel)">EROS</a></i> → CapROS</li>
<li><i><a href="Hydra_(operating_system)" title="Hydra (operating system)">Hydra</a></i></li>
<li><a href="L4_microkernel_family#High_assurance:_seL4" title="L4 microkernel family">seL4</a>^°</li>
<li><i><a href="Midori_(operating_system)" title="Midori (operating system)">Midori</a></i></li>
<li><i><a href="NLTSS" title="NLTSS">NLTSS</a></i></li>
<li><i><a href="HarmonyOS_NEXT" title="HarmonyOS NEXT">HarmonyOS NEXT</a> (<a href="OpenHarmony" title="OpenHarmony">OpenHarmony</a>, <a href="OpenHarmony#Oniro_OS" title="OpenHarmony">Oniro OS</a>)</i> → <i><a href="HarmonyOS" title="HarmonyOS">HarmonyOS</a></i></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="L4_microkernel_family" title="L4 microkernel family">L4</a> kernel</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="L4Linux" title="L4Linux">L<sup>4</sup>Linux</a>^°</li>
<li><a href="PikeOS" title="PikeOS">PikeOS</a>^</li>
<li><i><a href="REX_OS" title="REX OS">REX OS</a></i>^</li>
<li><a href="Wombat_(operating_system)" title="Wombat (operating system)">Wombat</a>^°</li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Java_virtual_machine" title="Java virtual machine">Java virtual machine</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="JavaOS" title="JavaOS">JavaOS</a></i> (<i><a href="JavaOS#Chorus/Jazz" title="JavaOS">Chorus/Jazz</a></i>^ integrates <i><a href="ChorusOS" title="ChorusOS">ChorusOS</a></i>^)</li>
<li><i><a href="JX_(operating_system)" title="JX (operating system)">JX</a></i>°</li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Macintosh" class="mw-redirect" title="Macintosh">Macintosh</a> hosted</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Unix-like13" scope="row" class="navbox-group" style="width:1%"><a href="Unix-like" title="Unix-like">Unix-like</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i><a href="MachTen" title="MachTen">MachTen</a></i></li>
<li><i><a href="MacMach" title="MacMach">MacMach</a></i></li></ul>
</div></td></tr></tbody></table><div>
<ul><li><i><a href="Copland_(operating_system)" title="Copland (operating system)">Copland</a></i></li>
<li><i><a href="Mac_OS_8#Mac_OS_8.6" title="Mac OS 8">Classic Mac OS</a></i> (<a href="PowerPC" title="PowerPC">PowerPC</a> kernel)</li></ul></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Psion_(company)" title="Psion (company)">Psion</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<li><i><a href="EPOC_(operating_system)" title="EPOC (operating system)">EPOC</a></i> → <i><a href="Symbian" title="Symbian">Symbian</a> OS</i>^°</li>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Amiga" title="Amiga">Amiga</a>-type</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="AmigaOS" title="AmigaOS">AmigaOS</a></li>
<li><a href="AROS_Research_Operating_System" title="AROS Research Operating System">AROS</a>°
<ul><li><a href="AROS_Research_Operating_System#AspireOS" title="AROS Research Operating System">AspireOS</a>°</li>
<li><a href="AROS_Research_Operating_System#Broadway" title="AROS Research Operating System">Broadway</a>°</li>
<li><a href="AROS_Research_Operating_System#Icaros_Desktop" title="AROS Research Operating System">Icaros Desktop</a>°</li></ul></li>
<li><a href="MorphOS" title="MorphOS">MorphOS</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Microsoft" title="Microsoft">Microsoft</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="Singularity_(operating_system)" title="Singularity (operating system)">Singularity</a></li>
<li><a href="ThreadX" title="ThreadX">ThreadX</a>^°</li>
<li><i><a href="Verve_(operating_system)" title="Verve (operating system)">Verve</a></i></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="AIM_alliance" title="AIM alliance">AIM alliance</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><i>Pink</i> → <i><a href="Taligent" title="Taligent">Taligent</a> OS</i> → <i><a href="Workplace_OS" title="Workplace OS">Workplace OS</a></i></li></ul>
</div></td></tr></tbody></table><div>
<ul><li><i><a href="Amoeba_(operating_system)" title="Amoeba (operating system)">Amoeba</a></i>°</li>
<li><i><a href="BeRTOS" title="BeRTOS">BeRTOS</a></i>^°</li>
<li><a href="ChibiOS/RT" title="ChibiOS/RT">ChibiOS/RT</a>^°</li>
<li><a href="FreeRTOS" title="FreeRTOS">FreeRTOS</a>^°</li>
<li><a href="HelenOS" title="HelenOS">HelenOS</a>°</li>
<li><a href="Micro-Controller_Operating_Systems" title="Micro-Controller Operating Systems">µC/OS</a>^°</li>
<li><a href="MQX" title="MQX">MQX</a>^</li>
<li><a href="OpenComRTOS" title="OpenComRTOS">OpenComRTOS</a>^</li>
<li><a href="Phantom_OS" title="Phantom OS">Phantom OS</a>^°</li>
<li><i><a href="RC_4000_multiprogramming_system" title="RC 4000 multiprogramming system">RC 4000</a></i></li>
<li><a href="SharpOS" title="SharpOS">SharpOS</a>°</li>
<li><i><a href="SPIN_(operating_system)" title="SPIN (operating system)">SPIN</a></i>°</li>
<li><i><a href="Thoth_(operating_system)" title="Thoth (operating system)">Thoth</a></i>^ → <i><a href="Harmony_(operating_system)" title="Harmony (operating system)">Harmony</a></i>^ → <i><a href="V_(operating_system)" title="V (operating system)">V</a></i></li>
<li><a href="Versatile_Real-Time_Executive" title="Versatile Real-Time Executive">VRTX</a>^</li></ul></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Software_framework" title="Software framework">Frameworks</a>, <a href="Software_development_kit" title="Software development kit">kits</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">
<li><a href="Cosmos_(operating_system)" title="Cosmos (operating system)">Cosmos</a>°</li>
<li><a href="Genode" title="Genode">Genode</a>°</li>
<li><a href="TI-RTOS" title="TI-RTOS">TI-RTOS</a>^°</li>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Programmer" title="Programmer">Developers</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">
<ul><li><a href="Gordon_Bell_(QNX)" title="Gordon Bell (QNX)">Gordon Bell</a></li>
<li><a href="Thomas_Bushnell" title="Thomas Bushnell">Thomas Bushnell</a></li>
<li><a href="David_Cheriton" title="David Cheriton">David Cheriton</a></li>
<li><a href="Dan_Dodge" title="Dan Dodge">Dan Dodge</a></li>
<li><a href="Per_Brinch_Hansen" title="Per Brinch Hansen">Per Brinch Hansen</a></li>
<li><a href="Gernot_Heiser" title="Gernot Heiser">Gernot Heiser</a></li>
<li><a href="Jochen_Liedtke" title="Jochen Liedtke">Jochen Liedtke</a></li>
<li><a href="James_G._Mitchell" title="James G. Mitchell">James G. Mitchell</a></li>
<li><a href="Ike_Nassi" title="Ike Nassi">Ike Nassi</a></li>
<li><a href="Richard_Rashid" title="Richard Rashid">Richard Rashid</a></li>
<li><a href="Andrew_S._Tanenbaum" title="Andrew S. Tanenbaum">Andrew S. Tanenbaum</a></li>
<li><a href="Avie_Tevanian" title="Avie Tevanian">Avie Tevanian</a></li>
<li><a href="William_Wulf" title="William Wulf">William Wulf</a></li></ul>
</div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>
<ul><li><i>Italics</i> <b>= discontinued</b></li>
<li><b>^ = <a href="Real-time_operating_system" title="Real-time operating system">Real-time</a></b></li>
<li><b>° = <a href="Open-source_software" title="Open-source software">Open-source software</a></b><br><span class="noviewer" typeof="mw:File"><span title="Category"></span></span> <b>Category: Microkernel-based operating systems</b> <span class="noviewer" typeof="mw:File"><span title="Category"></span></span> <b>Category: Microkernels</b></li></ul>
</div></td></tr></tbody></table></div>
<style data-mw-deduplicate="TemplateStyles:r1271159938">
/* start https://en.wikipedia.org/ */
.mw-parser-output .asbox{position:relative;overflow:hidden}.mw-parser-output .asbox table{background:transparent}.mw-parser-output .asbox p{margin:0}.mw-parser-output .asbox p+p{margin-top:0.25em}.mw-parser-output .asbox-body{font-style:italic}.mw-parser-output .asbox-note{font-size:smaller}.mw-parser-output .asbox .navbar{position:absolute;top:-0.75em;right:1em;display:none}.mw-parser-output :not(p):not(.asbox)+style+.asbox,.mw-parser-output :not(p):not(.asbox)+link+.asbox{margin-top:3em}
/* end https://en.wikipedia.org/ */
</style></div><!--htdig_noindex--><div><div class="zim-footer">
This article is issued from <a class="external text" title="Last edited on 2024-10-10" href="https://en.wikipedia.org/wiki/?title=KeyKOS&oldid=1250399146">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.
</div>
</div><!--/htdig_noindex--></div>
</div>
</main>
</div>
</div>
</div>
</body></html>