86 lines
3.3 KiB
HTML
86 lines
3.3 KiB
HTML
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<head>
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<title>sendfd(3) - Plan 9 from User Space</title>
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<meta content="text/html; charset=utf-8" http-equiv=Content-Type>
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</head>
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<body bgcolor=#ffffff>
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<table border=0 cellpadding=0 cellspacing=0 width=100%>
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<tr height=10><td>
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<tr><td width=20><td>
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<tr><td width=20><td><b>SENDFD(3)</b><td align=right><b>SENDFD(3)</b>
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<tr><td width=20><td colspan=2>
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<br>
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<p><font size=+1><b>NAME </b></font><br>
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<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
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sendfd, recvfd – pass file descriptors along Unix domain sockets<br>
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</table>
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<p><font size=+1><b>SYNOPSIS </b></font><br>
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<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
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<tt><font size=+1>#include <u.h>
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<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
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</font></tt>
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<tt><font size=+1>#include <libc.h>
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<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
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</font></tt>
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<tt><font size=+1>int sendfd(int socket, int fd)
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<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
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</font></tt>
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<tt><font size=+1>int recvfd(int socket)<br>
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</font></tt>
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</table>
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<p><font size=+1><b>DESCRIPTION </b></font><br>
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<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
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<i>Recvfd</i> and <i>sendfd</i> can be used to pass an open file descriptor
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over a Unix domain socket from one process to another. Since <a href="../man3/pipe.html"><i>pipe</i>(3)</a>
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is implemented with <a href="../man2/socketpair.html"><i>socketpair</i>(2)</a> instead of <a href="../man2/pipe.html"><i>pipe</i>(2)</a>, <i>socket</i> can
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be a file descriptor obtained from <a href="../man3/pipe.html"><i>pipe</i>(3)</a>.
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<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
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<i>Sendfd</i> sends the file descriptor <i>fd</i> along the socket to a process
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calling <i>recvfd</i> on the other end.
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<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
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It is assumed that the two sides have coordinated and agreed to
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transfer a file descriptor already, so that the <i>sendfd</i> is met
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with a <i>recvfd</i> instead of an ordinary <i>read</i>.
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<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
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The file descriptor number may change on its way between processes,
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but the kernel structure it represents will not.<br>
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</table>
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<p><font size=+1><b>SOURCE </b></font><br>
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<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
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<tt><font size=+1>/usr/local/plan9/src/lib9/sendfd.c<br>
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</font></tt>
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</table>
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<p><font size=+1><b>SEE ALSO </b></font><br>
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<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
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<a href="../man2/socketpair.html"><i>socketpair</i>(2)</a>, <i>sendmsg</i> in <a href="../man2/send.html"><i>send</i>(2)</a><br>
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</table>
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<td width=20>
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<tr height=20><td>
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</table>
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<!-- TRAILER -->
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<table border=0 cellpadding=0 cellspacing=0 width=100%>
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<tr height=15><td width=10><td><td width=10>
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<tr><td><td>
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<center>
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<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a>
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</center>
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</table>
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<!-- TRAILER -->
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</body></html>
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