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<span>Complementary system calls</span> </div> </a> <ul id="toc-Complementary_system_calls-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Requirements" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Requirements"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Requirements</span> </div> </a> <ul id="toc-Requirements-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span 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class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Splice_(system_call)" title="Special:EditPage/Splice (system call)">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Splice%22+system+call">"Splice" system call</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Splice%22+system+call+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Splice%22+system+call&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Splice%22+system+call+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Splice%22+system+call">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Splice%22+system+call&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">March 2011</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p><b><style data-mw-deduplicate="TemplateStyles:r886049734">.mw-parser-output .monospaced{font-family:monospace,monospace}</style><span class="monospaced">splice()</span></b> is a <a href="/wiki/Linux" title="Linux">Linux</a>-specific <a href="/wiki/System_call" title="System call">system call</a> that moves data between a <a href="/wiki/File_descriptor" title="File descriptor">file descriptor</a> and a pipe without a round trip to user space. The related system call <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced"><a class="mw-selflink-fragment" href="#Complementary_system_calls">vmsplice()</a></span> moves or copies data between a pipe and user space. Ideally, splice and vmsplice work by remapping pages and do not actually copy any data, which may improve <a href="/wiki/Input/output" title="Input/output">I/O</a> performance. As linear addresses do not necessarily correspond to contiguous physical addresses, this may not be possible in all cases and on all hardware combinations. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Workings">Workings</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=1" title="Edit section: Workings"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>With <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span>, one can move data from one file descriptor to another without incurring any copies from user space into kernel space, which is usually required to enforce system security and also to keep a simple interface for processes to read and write to files. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span> works by using the <a href="/wiki/Pipeline_(Unix)" title="Pipeline (Unix)">pipe buffer</a>. A pipe buffer is an in-kernel memory buffer that is opaque to the userspace process. A user process can splice the contents of a source file into this pipe buffer, then splice the pipe buffer into the destination file, all without moving any data through userspace. </p> <div class="mw-heading mw-heading2"><h2 id="Origins">Origins</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=2" title="Edit section: Origins"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/Linus_Torvalds" title="Linus Torvalds">Linus Torvalds</a> described <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span> in a 2006 email, which was included in a <a href="/wiki/KernelTrap" title="KernelTrap">KernelTrap</a> article.<sup id="cite_ref-:0_1-0" class="reference"><a href="#cite_note-:0-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/Linux" title="Linux">Linux</a> splice implementation borrows some ideas from an original proposal by <a href="/wiki/Larry_McVoy" title="Larry McVoy">Larry McVoy</a> in 1998.<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> The splice system calls first appeared in <a href="/wiki/Linux" title="Linux">Linux</a> kernel version 2.6.17<sup id="cite_ref-:0_1-1" class="reference"><a href="#cite_note-:0-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> and were written by <a href="/wiki/Jens_Axboe" title="Jens Axboe">Jens Axboe</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Prototype">Prototype</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=3" title="Edit section: Prototype"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span></span><span class="w"> </span><span class="kt">ssize_t</span><span class="w"> </span><span class="nf">splice</span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">fd_in</span><span class="p">,</span><span class="w"> </span><span class="n">loff_t</span><span class="w"> </span><span class="o">*</span><span class="n">off_in</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">fd_out</span><span class="p">,</span><span class="w"> </span><span class="n">loff_t</span><span class="w"> </span><span class="o">*</span><span class="n">off_out</span><span class="p">,</span><span class="w"> </span><span class="kt">size_t</span><span class="w"> </span><span class="n">len</span><span class="p">,</span><span class="w"> </span><span class="kt">unsigned</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">flags</span><span class="p">);</span> </pre></div> <p>Some constants that are of interest are: </p> <div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span></span><span class="cm">/* Splice flags (not laid down in stone yet). */</span> <span class="cp">#ifndef SPLICE_F_MOVE</span> <span class="cp">#define SPLICE_F_MOVE 0x01</span> <span class="cp">#endif</span> <span class="cp">#ifndef SPLICE_F_NONBLOCK</span> <span class="cp">#define SPLICE_F_NONBLOCK 0x02</span> <span class="cp">#endif</span> <span class="cp">#ifndef SPLICE_F_MORE</span> <span class="cp">#define SPLICE_F_MORE 0x04</span> <span class="cp">#endif</span> <span class="cp">#ifndef SPLICE_F_GIFT</span> <span class="cp">#define SPLICE_F_GIFT 0x08</span> <span class="cp">#endif</span> </pre></div> <div class="mw-heading mw-heading2"><h2 id="Example">Example</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=4" title="Edit section: Example"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>This is an example of splice in action: </p> <div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre><span></span><span class="cm">/* Transfer from disk to a log. */</span> <span class="kt">int</span><span class="w"> </span><span class="nf">log_blocks</span><span class="w"> </span><span class="p">(</span><span class="k">struct</span><span class="w"> </span><span class="nc">log_handle</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="n">handle</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">fd</span><span class="p">,</span><span class="w"> </span><span class="n">loff_t</span><span class="w"> </span><span class="n">offset</span><span class="p">,</span><span class="w"> </span><span class="kt">size_t</span><span class="w"> </span><span class="n">size</span><span class="p">)</span> <span class="p">{</span> <span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">filedes</span><span class="w"> </span><span class="p">[</span><span class="mi">2</span><span class="p">];</span> <span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">ret</span><span class="p">;</span> <span class="w"> </span><span class="kt">size_t</span><span class="w"> </span><span class="n">to_write</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">size</span><span class="p">;</span> <span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">pipe</span><span class="w"> </span><span class="p">(</span><span class="n">filedes</span><span class="p">);</span> <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">ret</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span> <span class="w"> </span><span class="k">goto</span><span class="w"> </span><span class="n">out</span><span class="p">;</span> <span class="w"> </span><span class="cm">/* splice the file into the pipe (data in kernel memory). */</span> <span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">to_write</span><span class="w"> </span><span class="o">></span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="p">{</span> <span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">splice</span><span class="w"> </span><span class="p">(</span><span class="n">fd</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">offset</span><span class="p">,</span><span class="w"> </span><span class="n">filedes</span><span class="w"> </span><span class="p">[</span><span class="mi">1</span><span class="p">],</span><span class="w"> </span><span class="nb">NULL</span><span class="p">,</span><span class="w"> </span><span class="n">to_write</span><span class="p">,</span> <span class="w"> </span><span class="n">SPLICE_F_MORE</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="n">SPLICE_F_MOVE</span><span class="p">);</span> <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">ret</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span> <span class="w"> </span><span class="k">goto</span><span class="w"> </span><span class="n">pipe</span><span class="p">;</span> <span class="w"> </span><span class="k">else</span> <span class="w"> </span><span class="n">to_write</span><span class="w"> </span><span class="o">-=</span><span class="w"> </span><span class="n">ret</span><span class="p">;</span> <span class="w"> </span><span class="p">}</span> <span class="w"> </span><span class="n">to_write</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">size</span><span class="p">;</span> <span class="w"> </span><span class="cm">/* splice the data in the pipe (in kernel memory) into the file. */</span> <span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">to_write</span><span class="w"> </span><span class="o">></span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="p">{</span> <span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">splice</span><span class="w"> </span><span class="p">(</span><span class="n">filedes</span><span class="w"> </span><span class="p">[</span><span class="mi">0</span><span class="p">],</span><span class="w"> </span><span class="nb">NULL</span><span class="p">,</span><span class="w"> </span><span class="n">handle</span><span class="o">-></span><span class="n">fd</span><span class="p">,</span> <span class="w"> </span><span class="o">&</span><span class="p">(</span><span class="n">handle</span><span class="o">-></span><span class="n">fd_offset</span><span class="p">),</span><span class="w"> </span><span class="n">to_write</span><span class="p">,</span> <span class="w"> </span><span class="n">SPLICE_F_MORE</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="n">SPLICE_F_MOVE</span><span class="p">);</span> <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">ret</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span> <span class="w"> </span><span class="k">goto</span><span class="w"> </span><span class="n">pipe</span><span class="p">;</span> <span class="w"> </span><span class="k">else</span> <span class="w"> </span><span class="n">to_write</span><span class="w"> </span><span class="o">-=</span><span class="w"> </span><span class="n">ret</span><span class="p">;</span> <span class="w"> </span><span class="p">}</span> <span class="nl">pipe</span><span class="p">:</span> <span class="w"> </span><span class="n">close</span><span class="w"> </span><span class="p">(</span><span class="n">filedes</span><span class="w"> </span><span class="p">[</span><span class="mi">0</span><span class="p">]);</span> <span class="w"> </span><span class="n">close</span><span class="w"> </span><span class="p">(</span><span class="n">filedes</span><span class="w"> </span><span class="p">[</span><span class="mi">1</span><span class="p">]);</span> <span class="nl">out</span><span class="p">:</span> <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">ret</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span> <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="o">-</span><span class="n">errno</span><span class="p">;</span> <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span> <span class="p">}</span> </pre></div> <div class="mw-heading mw-heading2"><h2 id="Complementary_system_calls">Complementary system calls</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=5" title="Edit section: Complementary system calls"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span> is one of three system calls that complete the <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span> architecture. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">vmsplice()</span> can map an application data area into a pipe (or vice versa), thus allowing transfers between pipes and user memory where <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">sys_splice()</span> transfers between a file descriptor and a pipe. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">tee()</span> is the last part of the trilogy. It duplicates one pipe to another, enabling forks in the way applications are connected with pipes. </p> <div class="mw-heading mw-heading2"><h2 id="Requirements">Requirements</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=6" title="Edit section: Requirements"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>When using <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span> with sockets, the network controller (NIC) should support DMA, otherwise splice() will not deliver a large performance improvement. The reason for this is that each page of the pipe will just fill up to frame size (1460 bytes of the available 4096 bytes per page). <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span> does not support UDP sockets. </p><p>Not all filesystem types support <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span>. Also, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">AF_UNIX</span> sockets do not support <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">splice()</span>. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=7" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/System_call" title="System call">System call</a></li> <li><a href="/wiki/Zero-copy" title="Zero-copy">Zero-copy</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Splice_(system_call)&action=edit&section=8" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.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}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-:0-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_1-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.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("//upload.wikimedia.org/wikipedia/commons/6/65/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("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/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}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20130521163124/http://kerneltrap.org/node/6505">"Linux: Explaining splice() and tee()"</a>. kerneltrap.org. 2006-04-21. Archived from <a rel="nofollow" class="external text" href="http://kerneltrap.org/node/6505">the original</a> on 2013-05-21<span class="reference-accessdate">. Retrieved <span class="nowrap">2014-04-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Linux%3A+Explaining+splice%28%29+and+tee%28%29&rft.pub=kerneltrap.org&rft.date=2006-04-21&rft_id=http%3A%2F%2Fkerneltrap.org%2Fnode%2F6505&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASplice+%28system+call%29" class="Z3988"></span></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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160304171221/http://ftp.tux.org/pub/sites/ftp.bitmover.com/pub/splice.ps">"Archived copy"</a>. 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