git-svn-id: svn://10.65.10.50/branches/R_10_00@23289 c028cbd2-c16b-5b4b-a496-9718f37d4682
		
			
				
	
	
		
			942 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
			
		
		
	
	
			942 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
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    "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
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<head>
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<meta http-equiv="Content-Type" content="application/xhtml+xml; charset=UTF-8" />
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<meta name="generator" content="AsciiDoc 8.6.3" />
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<title>zmq(7)</title>
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<style type="text/css">
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/* Sans-serif font. */
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h1, h2, h3, h4, h5, h6,
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div.title, caption.title,
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thead, p.table.header,
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div#toctitle,
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span#author, span#revnumber, span#revdate, span#revremark,
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div#footer {
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  font-family: Arial,Helvetica,sans-serif;
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}
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/* Serif font. */
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div.sectionbody {
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  font-family: Georgia,"Times New Roman",Times,serif;
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}
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/* Monospace font. */
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tt {
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  font-size: inherit;
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}
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body {
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  margin: 1em 5% 1em 5%;
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}
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a {
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  color: blue;
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  text-decoration: underline;
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}
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a:visited {
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  color: fuchsia;
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}
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em {
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  font-style: italic;
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  color: navy;
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}
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strong {
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  font-weight: bold;
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  color: #083194;
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}
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tt {
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  font-size: inherit;
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  color: navy;
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}
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h1, h2, h3, h4, h5, h6 {
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  color: #527bbd;
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  margin-top: 1.2em;
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  margin-bottom: 0.5em;
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  line-height: 1.3;
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}
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h1, h2, h3 {
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  border-bottom: 2px solid silver;
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}
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h2 {
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  padding-top: 0.5em;
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}
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h3 {
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  float: left;
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}
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h3 + * {
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  clear: left;
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}
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div.sectionbody {
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  margin-left: 0;
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}
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hr {
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  border: 1px solid silver;
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}
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p {
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  margin-top: 0.5em;
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  margin-bottom: 0.5em;
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}
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ul, ol, li > p {
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  margin-top: 0;
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}
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ul > li     { color: #aaa; }
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ul > li > * { color: black; }
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pre {
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  padding: 0;
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  margin: 0;
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}
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span#author {
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  color: #527bbd;
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  font-weight: bold;
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  font-size: 1.1em;
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}
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span#email {
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}
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span#revnumber, span#revdate, span#revremark {
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}
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div#footer {
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  font-size: small;
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  border-top: 2px solid silver;
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  padding-top: 0.5em;
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  margin-top: 4.0em;
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}
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div#footer-text {
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  float: left;
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  padding-bottom: 0.5em;
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}
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div#footer-badges {
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  float: right;
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  padding-bottom: 0.5em;
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}
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div#preamble {
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  margin-top: 1.5em;
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  margin-bottom: 1.5em;
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}
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div.tableblock, div.imageblock, div.exampleblock, div.verseblock,
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div.quoteblock, div.literalblock, div.listingblock, div.sidebarblock,
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div.admonitionblock {
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  margin-top: 1.0em;
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  margin-bottom: 1.5em;
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}
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div.admonitionblock {
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  margin-top: 2.0em;
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  margin-bottom: 2.0em;
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  margin-right: 10%;
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  color: #606060;
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}
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div.content { /* Block element content. */
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  padding: 0;
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}
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/* Block element titles. */
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div.title, caption.title {
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  color: #527bbd;
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  font-weight: bold;
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  text-align: left;
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  margin-top: 1.0em;
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  margin-bottom: 0.5em;
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}
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div.title + * {
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  margin-top: 0;
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}
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td div.title:first-child {
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  margin-top: 0.0em;
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}
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div.content div.title:first-child {
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  margin-top: 0.0em;
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}
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div.content + div.title {
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  margin-top: 0.0em;
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}
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div.sidebarblock > div.content {
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  background: #ffffee;
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  border: 1px solid #dddddd;
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  border-left: 4px solid #f0f0f0;
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  padding: 0.5em;
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}
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div.listingblock > div.content {
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  border: 1px solid #dddddd;
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  border-left: 5px solid #f0f0f0;
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  background: #f8f8f8;
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  padding: 0.5em;
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}
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div.quoteblock, div.verseblock {
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  padding-left: 1.0em;
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  margin-left: 1.0em;
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  margin-right: 10%;
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  border-left: 5px solid #f0f0f0;
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  color: #777777;
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}
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div.quoteblock > div.attribution {
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  padding-top: 0.5em;
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  text-align: right;
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}
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div.verseblock > pre.content {
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  font-family: inherit;
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  font-size: inherit;
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}
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div.verseblock > div.attribution {
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  padding-top: 0.75em;
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  text-align: left;
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}
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/* DEPRECATED: Pre version 8.2.7 verse style literal block. */
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div.verseblock + div.attribution {
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  text-align: left;
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}
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div.admonitionblock .icon {
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  vertical-align: top;
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  font-size: 1.1em;
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  font-weight: bold;
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  text-decoration: underline;
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  color: #527bbd;
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  padding-right: 0.5em;
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}
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div.admonitionblock td.content {
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  padding-left: 0.5em;
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  border-left: 3px solid #dddddd;
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}
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div.exampleblock > div.content {
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  border-left: 3px solid #dddddd;
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  padding-left: 0.5em;
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}
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div.imageblock div.content { padding-left: 0; }
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span.image img { border-style: none; }
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a.image:visited { color: white; }
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dl {
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  margin-top: 0.8em;
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  margin-bottom: 0.8em;
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}
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dt {
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  margin-top: 0.5em;
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  margin-bottom: 0;
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  font-style: normal;
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  color: navy;
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}
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dd > *:first-child {
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  margin-top: 0.1em;
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}
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ul, ol {
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    list-style-position: outside;
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}
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ol.arabic {
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  list-style-type: decimal;
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}
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ol.loweralpha {
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						|
  list-style-type: lower-alpha;
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}
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ol.upperalpha {
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						|
  list-style-type: upper-alpha;
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}
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ol.lowerroman {
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  list-style-type: lower-roman;
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}
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ol.upperroman {
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  list-style-type: upper-roman;
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}
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div.compact ul, div.compact ol,
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div.compact p, div.compact p,
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div.compact div, div.compact div {
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  margin-top: 0.1em;
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  margin-bottom: 0.1em;
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}
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div.tableblock > table {
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  border: 3px solid #527bbd;
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}
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thead, p.table.header {
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  font-weight: bold;
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						|
  color: #527bbd;
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}
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tfoot {
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  font-weight: bold;
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}
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td > div.verse {
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  white-space: pre;
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}
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p.table {
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  margin-top: 0;
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}
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/* Because the table frame attribute is overriden by CSS in most browsers. */
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div.tableblock > table[frame="void"] {
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  border-style: none;
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}
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div.tableblock > table[frame="hsides"] {
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						|
  border-left-style: none;
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						|
  border-right-style: none;
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}
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div.tableblock > table[frame="vsides"] {
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  border-top-style: none;
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  border-bottom-style: none;
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}
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div.hdlist {
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  margin-top: 0.8em;
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						|
  margin-bottom: 0.8em;
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						|
}
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						|
div.hdlist tr {
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  padding-bottom: 15px;
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						|
}
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						|
dt.hdlist1.strong, td.hdlist1.strong {
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						|
  font-weight: bold;
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}
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td.hdlist1 {
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  vertical-align: top;
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						|
  font-style: normal;
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						|
  padding-right: 0.8em;
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						|
  color: navy;
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}
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td.hdlist2 {
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  vertical-align: top;
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}
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						|
div.hdlist.compact tr {
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  margin: 0;
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						|
  padding-bottom: 0;
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						|
}
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.comment {
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						|
  background: yellow;
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						|
}
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						|
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.footnote, .footnoteref {
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						|
  font-size: 0.8em;
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						|
}
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						|
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						|
span.footnote, span.footnoteref {
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						|
  vertical-align: super;
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						|
}
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#footnotes {
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						|
  margin: 20px 0 20px 0;
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						|
  padding: 7px 0 0 0;
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						|
}
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						|
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						|
#footnotes div.footnote {
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						|
  margin: 0 0 5px 0;
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						|
}
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#footnotes hr {
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						|
  border: none;
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						|
  border-top: 1px solid silver;
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						|
  height: 1px;
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						|
  text-align: left;
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						|
  margin-left: 0;
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						|
  width: 20%;
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  min-width: 100px;
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}
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div.colist td {
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  padding-right: 0.5em;
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						|
  padding-bottom: 0.3em;
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						|
  vertical-align: top;
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						|
}
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div.colist td img {
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  margin-top: 0.3em;
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}
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@media print {
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  div#footer-badges { display: none; }
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						|
}
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div#toc {
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						|
  margin-bottom: 2.5em;
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						|
}
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div#toctitle {
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						|
  color: #527bbd;
 | 
						|
  font-size: 1.1em;
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						|
  font-weight: bold;
 | 
						|
  margin-top: 1.0em;
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						|
  margin-bottom: 0.1em;
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						|
}
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						|
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div.toclevel1, div.toclevel2, div.toclevel3, div.toclevel4 {
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  margin-top: 0;
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  margin-bottom: 0;
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}
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div.toclevel2 {
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  margin-left: 2em;
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  font-size: 0.9em;
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}
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						|
div.toclevel3 {
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						|
  margin-left: 4em;
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						|
  font-size: 0.9em;
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}
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div.toclevel4 {
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						|
  margin-left: 6em;
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						|
  font-size: 0.9em;
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						|
}
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						|
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						|
/* Overrides for manpage documents */
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h1 {
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						|
  padding-top: 0.5em;
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						|
  padding-bottom: 0.5em;
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						|
  border-top: 2px solid silver;
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						|
  border-bottom: 2px solid silver;
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						|
}
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						|
h2 {
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						|
  border-style: none;
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						|
}
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						|
div.sectionbody {
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						|
  margin-left: 5%;
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						|
}
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						|
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@media print {
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						|
  div#toc { display: none; }
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						|
}
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						|
 | 
						|
</style>
 | 
						|
<script type="text/javascript">
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/*<+'])');
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    // Function that scans the DOM tree for header elements (the DOM2
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    // nodeIterator API would be a better technique but not supported by all
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						|
    // browsers).
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						|
    var iterate = function (el) {
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						|
      for (var i = el.firstChild; i != null; i = i.nextSibling) {
 | 
						|
        if (i.nodeType == 1 /* Node.ELEMENT_NODE */) {
 | 
						|
          var mo = re.exec(i.tagName);
 | 
						|
          if (mo && (i.getAttribute("class") || i.getAttribute("className")) != "float") {
 | 
						|
            result[result.length] = new TocEntry(i, getText(i), mo[1]-1);
 | 
						|
          }
 | 
						|
          iterate(i);
 | 
						|
        }
 | 
						|
      }
 | 
						|
    }
 | 
						|
    iterate(el);
 | 
						|
    return result;
 | 
						|
  }
 | 
						|
 | 
						|
  var toc = document.getElementById("toc");
 | 
						|
  var entries = tocEntries(document.getElementById("content"), toclevels);
 | 
						|
  for (var i = 0; i < entries.length; ++i) {
 | 
						|
    var entry = entries[i];
 | 
						|
    if (entry.element.id == "")
 | 
						|
      entry.element.id = "_toc_" + i;
 | 
						|
    var a = document.createElement("a");
 | 
						|
    a.href = "#" + entry.element.id;
 | 
						|
    a.appendChild(document.createTextNode(entry.text));
 | 
						|
    var div = document.createElement("div");
 | 
						|
    div.appendChild(a);
 | 
						|
    div.className = "toclevel" + entry.toclevel;
 | 
						|
    toc.appendChild(div);
 | 
						|
  }
 | 
						|
  if (entries.length == 0)
 | 
						|
    toc.parentNode.removeChild(toc);
 | 
						|
},
 | 
						|
 | 
						|
 | 
						|
/////////////////////////////////////////////////////////////////////
 | 
						|
// Footnotes generator
 | 
						|
/////////////////////////////////////////////////////////////////////
 | 
						|
 | 
						|
/* Based on footnote generation code from:
 | 
						|
 * http://www.brandspankingnew.net/archive/2005/07/format_footnote.html
 | 
						|
 */
 | 
						|
 | 
						|
footnotes: function () {
 | 
						|
  var cont = document.getElementById("content");
 | 
						|
  var noteholder = document.getElementById("footnotes");
 | 
						|
  var spans = cont.getElementsByTagName("span");
 | 
						|
  var refs = {};
 | 
						|
  var n = 0;
 | 
						|
  for (i=0; i<spans.length; i++) {
 | 
						|
    if (spans[i].className == "footnote") {
 | 
						|
      n++;
 | 
						|
      // Use [\s\S] in place of . so multi-line matches work.
 | 
						|
      // Because JavaScript has no s (dotall) regex flag.
 | 
						|
      note = spans[i].innerHTML.match(/\s*\[([\s\S]*)]\s*/)[1];
 | 
						|
      noteholder.innerHTML +=
 | 
						|
        "<div class='footnote' id='_footnote_" + n + "'>" +
 | 
						|
        "<a href='#_footnoteref_" + n + "' title='Return to text'>" +
 | 
						|
        n + "</a>. " + note + "</div>";
 | 
						|
      spans[i].innerHTML =
 | 
						|
        "[<a id='_footnoteref_" + n + "' href='#_footnote_" + n +
 | 
						|
        "' title='View footnote' class='footnote'>" + n + "</a>]";
 | 
						|
      var id =spans[i].getAttribute("id");
 | 
						|
      if (id != null) refs["#"+id] = n;
 | 
						|
    }
 | 
						|
  }
 | 
						|
  if (n == 0)
 | 
						|
    noteholder.parentNode.removeChild(noteholder);
 | 
						|
  else {
 | 
						|
    // Process footnoterefs.
 | 
						|
    for (i=0; i<spans.length; i++) {
 | 
						|
      if (spans[i].className == "footnoteref") {
 | 
						|
        var href = spans[i].getElementsByTagName("a")[0].getAttribute("href");
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        href = href.match(/#.*/)[0];  // Because IE return full URL.
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        n = refs[href];
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        spans[i].innerHTML =
 | 
						|
          "[<a href='#_footnote_" + n +
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          "' title='View footnote' class='footnote'>" + n + "</a>]";
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      }
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    }
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  }
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}
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}
 | 
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/*]]>*/
 | 
						|
</script>
 | 
						|
</head>
 | 
						|
<body class="manpage">
 | 
						|
<div id="header">
 | 
						|
<h1>
 | 
						|
zmq(7) Manual Page
 | 
						|
</h1>
 | 
						|
<h2>NAME</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<p>zmq -
 | 
						|
   0MQ lightweight messaging kernel
 | 
						|
</p>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div id="content">
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_synopsis">SYNOPSIS</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p><strong>#include <zmq.h></strong></p></div>
 | 
						|
<div class="paragraph"><p><strong>cc</strong> [<em>flags</em>] <em>files</em> <strong>-lzmq</strong> [<em>libraries</em>]</p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_description">DESCRIPTION</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>The ØMQ lightweight messaging kernel is a library which extends the standard
 | 
						|
socket interfaces with features traditionally provided by specialised
 | 
						|
<em>messaging middleware</em> products. ØMQ sockets provide an abstraction of
 | 
						|
asynchronous <em>message queues</em>, multiple <em>messaging patterns</em>, message
 | 
						|
filtering (<em>subscriptions</em>), seamless access to multiple <em>transport protocols</em>
 | 
						|
and more.</p></div>
 | 
						|
<div class="paragraph"><p>This documentation presents an overview of ØMQ concepts, describes how ØMQ
 | 
						|
abstracts standard sockets and provides a reference manual for the functions
 | 
						|
provided by the ØMQ library.</p></div>
 | 
						|
<div class="sect2">
 | 
						|
<h3 id="_context">Context</h3>
 | 
						|
<div class="paragraph"><p>Before using any ØMQ library functions you must create a ØMQ <em>context</em>. When
 | 
						|
you exit your application you must destroy the <em>context</em>. These functions let
 | 
						|
you work with <em>contexts</em>:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Create a new ØMQ context
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_ctx_new.html">zmq_ctx_new(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Work with context properties
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_ctx_set.html">zmq_ctx_set(3)</a>
 | 
						|
    <a href="zmq_ctx_get.html">zmq_ctx_get(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Destroy a ØMQ context
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_ctx_term.html">zmq_ctx_term(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
<div class="paragraph"><p>These deprecated functions let you create and destroy <em>contexts</em>:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Initialise ØMQ context
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_init.html">zmq_init(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Terminate ØMQ context
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_term.html">zmq_term(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
<div class="sect3">
 | 
						|
<h4 id="_thread_safety">Thread safety</h4>
 | 
						|
<div class="paragraph"><p>A ØMQ <em>context</em> is thread safe and may be shared among as many application
 | 
						|
threads as necessary, without any additional locking required on the part of
 | 
						|
the caller.</p></div>
 | 
						|
<div class="paragraph"><p>Individual ØMQ <em>sockets</em> are <em>not</em> thread safe except in the case where full
 | 
						|
memory barriers are issued when migrating a socket from one thread to another.
 | 
						|
In practice this means applications can create a socket in one thread with
 | 
						|
<em>zmq_socket()</em> and then pass it to a <em>newly created</em> thread as part of thread
 | 
						|
initialization, for example via a structure passed as an argument to
 | 
						|
<em>pthread_create()</em>.</p></div>
 | 
						|
</div>
 | 
						|
<div class="sect3">
 | 
						|
<h4 id="_multiple_contexts">Multiple contexts</h4>
 | 
						|
<div class="paragraph"><p>Multiple <em>contexts</em> may coexist within a single application. Thus, an
 | 
						|
application can use ØMQ directly and at the same time make use of any number of
 | 
						|
additional libraries or components which themselves make use of ØMQ as long as
 | 
						|
the above guidelines regarding thread safety are adhered to.</p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect2">
 | 
						|
<h3 id="_messages">Messages</h3>
 | 
						|
<div class="paragraph"><p>A ØMQ message is a discrete unit of data passed between applications or
 | 
						|
components of the same application. ØMQ messages have no internal structure and
 | 
						|
from the point of view of ØMQ itself they are considered to be opaque binary
 | 
						|
data.</p></div>
 | 
						|
<div class="paragraph"><p>The following functions are provided to work with messages:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Initialise a message
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_init.html">zmq_msg_init(3)</a>
 | 
						|
    <a href="zmq_msg_init_size.html">zmq_msg_init_size(3)</a>
 | 
						|
    <a href="zmq_msg_init_data.html">zmq_msg_init_data(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Sending and receiving a message
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_send.html">zmq_msg_send(3)</a>
 | 
						|
    <a href="zmq_msg_recv.html">zmq_msg_recv(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Release a message
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_close.html">zmq_msg_close(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Access message content
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_data.html">zmq_msg_data(3)</a>
 | 
						|
    <a href="zmq_msg_size.html">zmq_msg_size(3)</a>
 | 
						|
    <a href="zmq_msg_more.html">zmq_msg_more(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Work with message properties
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_get.html">zmq_msg_get(3)</a>
 | 
						|
    <a href="zmq_msg_set.html">zmq_msg_set(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Message manipulation
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_copy.html">zmq_msg_copy(3)</a>
 | 
						|
    <a href="zmq_msg_move.html">zmq_msg_move(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
</div>
 | 
						|
<div class="sect2">
 | 
						|
<h3 id="_sockets">Sockets</h3>
 | 
						|
<div class="paragraph"><p>ØMQ sockets present an abstraction of a asynchronous <em>message queue</em>, with the
 | 
						|
exact queueing semantics depending on the socket type in use. See
 | 
						|
<a href="zmq_socket.html">zmq_socket(3)</a> for the socket types provided.</p></div>
 | 
						|
<div class="paragraph"><p>The following functions are provided to work with sockets:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Creating a socket
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_socket.html">zmq_socket(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Closing a socket
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_close.html">zmq_close(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Manipulating socket options
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_getsockopt.html">zmq_getsockopt(3)</a>
 | 
						|
    <a href="zmq_setsockopt.html">zmq_setsockopt(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Establishing a message flow
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_bind.html">zmq_bind(3)</a>
 | 
						|
    <a href="zmq_connect.html">zmq_connect(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Sending and receiving messages
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_msg_send.html">zmq_msg_send(3)</a>
 | 
						|
    <a href="zmq_msg_recv.html">zmq_msg_recv(3)</a>
 | 
						|
    <a href="zmq_send.html">zmq_send(3)</a>
 | 
						|
    <a href="zmq_recv.html">zmq_recv(3)</a>
 | 
						|
    <a href="zmq_send_const.html">zmq_send_const(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
<div class="paragraph"><p>Monitoring socket events:
 | 
						|
    <a href="zmq_socket_monitor.html">zmq_socket_monitor(3)</a></p></div>
 | 
						|
<div class="paragraph"><div class="title">Input/output multiplexing</div><p>ØMQ provides a mechanism for applications to multiplex input/output events over
 | 
						|
a set containing both ØMQ sockets and standard sockets. This mechanism mirrors
 | 
						|
the standard <em>poll()</em> system call, and is described in detail in
 | 
						|
<a href="zmq_poll.html">zmq_poll(3)</a>.</p></div>
 | 
						|
</div>
 | 
						|
<div class="sect2">
 | 
						|
<h3 id="_transports">Transports</h3>
 | 
						|
<div class="paragraph"><p>A ØMQ socket can use multiple different underlying transport mechanisms.
 | 
						|
Each transport mechanism is suited to a particular purpose and has its own
 | 
						|
advantages and drawbacks.</p></div>
 | 
						|
<div class="paragraph"><p>The following transport mechanisms are provided:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Unicast transport using TCP
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_tcp.html">zmq_tcp(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Reliable multicast transport using PGM
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_pgm.html">zmq_pgm(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Local inter-process communication transport
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_ipc.html">zmq_ipc(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Local in-process (inter-thread) communication transport
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_inproc.html">zmq_inproc(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
</div>
 | 
						|
<div class="sect2">
 | 
						|
<h3 id="_proxies">Proxies</h3>
 | 
						|
<div class="paragraph"><p>ØMQ provides <em>proxies</em> to create fanout and fan-in topologies. A proxy connects
 | 
						|
a <em>frontend</em> socket to a <em>backend</em> socket and switches all messages between the
 | 
						|
two sockets, opaquely. A proxy may optionally capture all traffic to a third
 | 
						|
socket. To start a proxy in an application thread, use <a href="zmq_proxy.html">zmq_proxy(3)</a>.</p></div>
 | 
						|
</div>
 | 
						|
<div class="sect2">
 | 
						|
<h3 id="_security">Security</h3>
 | 
						|
<div class="paragraph"><p>A ØMQ socket can select a security mechanism. Both peers must use the same
 | 
						|
security mechanism.</p></div>
 | 
						|
<div class="paragraph"><p>The following security mechanisms are provided for IPC and TCP connections:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Null security
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_null.html">zmq_null(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Plain-text authentication using username and password
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_plain.html">zmq_plain(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
<dt class="hdlist1">
 | 
						|
Elliptic curve authentication and encryption
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_curve.html">zmq_curve(7)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
<div class="paragraph"><p>Generate a CURVE keypair in armored text format:
 | 
						|
    <a href="zmq_curve_keypair.html">zmq_curve_keypair(3)</a></p></div>
 | 
						|
<div class="paragraph"><p>Convert an armored key into a 32-byte binary key:
 | 
						|
    <a href="zmq_z85_decode.html">zmq_z85_decode(3)</a></p></div>
 | 
						|
<div class="paragraph"><p>Convert a 32-byte binary CURVE key to an armored text string:
 | 
						|
    <a href="zmq_z85_encode.html">zmq_z85_encode(3)</a></p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_error_handling">ERROR HANDLING</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>The ØMQ library functions handle errors using the standard conventions found on
 | 
						|
POSIX systems. Generally, this means that upon failure a ØMQ library function
 | 
						|
shall return either a NULL value (if returning a pointer) or a negative value
 | 
						|
(if returning an integer), and the actual error code shall be stored in the
 | 
						|
<em>errno</em> variable.</p></div>
 | 
						|
<div class="paragraph"><p>On non-POSIX systems some users may experience issues with retrieving the
 | 
						|
correct value of the <em>errno</em> variable. The <em>zmq_errno()</em> function is provided
 | 
						|
to assist in these cases; for details refer to <a href="zmq_errno.html">zmq_errno(3)</a>.</p></div>
 | 
						|
<div class="paragraph"><p>The <em>zmq_strerror()</em> function is provided to translate ØMQ-specific error codes
 | 
						|
into error message strings; for details refer to <a href="zmq_strerror.html">zmq_strerror(3)</a>.</p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_miscellaneous">MISCELLANEOUS</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>The following miscellaneous functions are provided:</p></div>
 | 
						|
<div class="dlist"><dl>
 | 
						|
<dt class="hdlist1">
 | 
						|
Report ØMQ library version
 | 
						|
</dt>
 | 
						|
<dd>
 | 
						|
<p>
 | 
						|
    <a href="zmq_version.html">zmq_version(3)</a>
 | 
						|
</p>
 | 
						|
</dd>
 | 
						|
</dl></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_language_bindings">LANGUAGE BINDINGS</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>The ØMQ library provides interfaces suitable for calling from programs in any
 | 
						|
language; this documentation documents those interfaces as they would be used
 | 
						|
by C programmers. The intent is that programmers using ØMQ from other languages
 | 
						|
shall refer to this documentation alongside any documentation provided by the
 | 
						|
vendor of their language binding.</p></div>
 | 
						|
<div class="paragraph"><p>Language bindings (C++, Python, PHP, Ruby, Java and more) are provided by
 | 
						|
members of the ØMQ community and pointers can be found on the ØMQ website.</p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_authors">AUTHORS</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>This page was written by the ØMQ community. To make a change please
 | 
						|
read the ØMQ Contribution Policy at <a href="http://www.zeromq.org/docs:contributing">http://www.zeromq.org/docs:contributing</a>.</p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_resources">RESOURCES</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>Main web site: <a href="http://www.zeromq.org/">http://www.zeromq.org/</a></p></div>
 | 
						|
<div class="paragraph"><p>Report bugs to the ØMQ development mailing list: <<a href="mailto:zeromq-dev@lists.zeromq.org">zeromq-dev@lists.zeromq.org</a>></p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
<div class="sect1">
 | 
						|
<h2 id="_copying">COPYING</h2>
 | 
						|
<div class="sectionbody">
 | 
						|
<div class="paragraph"><p>Free use of this software is granted under the terms of the GNU Lesser General
 | 
						|
Public License (LGPL). For details see the files <tt>COPYING</tt> and <tt>COPYING.LESSER</tt>
 | 
						|
included with the ØMQ distribution.</p></div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
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ØMQ 4.0.4<br />
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Last updated 2013-11-13 12:57:50 EST
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