196 lines
4.4 KiB
HTML
196 lines
4.4 KiB
HTML
|
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
|
<HTML><HEAD><TITLE>Man page of BINDRESVPORT</TITLE>
|
|
</HEAD><BODY>
|
|
<H1>BINDRESVPORT</H1>
|
|
Section: Linux Programmer's Manual (3)<BR>Updated: 2017-09-15<BR><A HREF="#index">Index</A>
|
|
<A HREF="/cgi-bin/man/man2html">Return to Main Contents</A><HR>
|
|
|
|
<A NAME="lbAB"> </A>
|
|
<H2>NAME</H2>
|
|
|
|
bindresvport - bind a socket to a privileged IP port
|
|
<A NAME="lbAC"> </A>
|
|
<H2>SYNOPSIS</H2>
|
|
|
|
<PRE>
|
|
<B>#include <<A HREF="file:///usr/include/sys/types.h">sys/types.h</A>></B>
|
|
<B>#include <<A HREF="file:///usr/include/netinet/in.h">netinet/in.h</A>></B>
|
|
|
|
<B>int bindresvport(int </B><I>sockfd</I><B>, struct sockaddr_in *</B><I>sin</I><B>);</B>
|
|
</PRE>
|
|
|
|
<A NAME="lbAD"> </A>
|
|
<H2>DESCRIPTION</H2>
|
|
|
|
<P>
|
|
|
|
<B>bindresvport</B>()
|
|
|
|
is used to bind the socket referred to by the
|
|
file descriptor
|
|
<I>sockfd</I>
|
|
|
|
to a privileged anonymous IP port,
|
|
that is, a port number arbitrarily selected from the range 512 to 1023.
|
|
|
|
<P>
|
|
|
|
If the
|
|
<B><A HREF="/cgi-bin/man/man2html?2+bind">bind</A></B>(2)
|
|
|
|
performed by
|
|
<B>bindresvport</B>()
|
|
|
|
is successful, and
|
|
<I>sin</I>
|
|
|
|
is not NULL, then
|
|
<I>sin->sin_port</I>
|
|
|
|
returns the port number actually allocated.
|
|
<P>
|
|
|
|
<I>sin</I>
|
|
|
|
can be NULL, in which case
|
|
<I>sin->sin_family</I>
|
|
|
|
is implicitly taken to be
|
|
<B>AF_INET</B>.
|
|
|
|
However, in this case,
|
|
<B>bindresvport</B>()
|
|
|
|
has no way to return the port number actually allocated.
|
|
(This information can later be obtained using
|
|
<B><A HREF="/cgi-bin/man/man2html?2+getsockname">getsockname</A></B>(2).)
|
|
|
|
<A NAME="lbAE"> </A>
|
|
<H2>RETURN VALUE</H2>
|
|
|
|
<B>bindresvport</B>()
|
|
|
|
returns 0 on success; otherwise -1 is returned and
|
|
<I>errno</I>
|
|
|
|
set to indicate the cause of the error.
|
|
<A NAME="lbAF"> </A>
|
|
<H2>ERRORS</H2>
|
|
|
|
<B>bindresvport</B>()
|
|
|
|
can fail for any of the same reasons as
|
|
<B><A HREF="/cgi-bin/man/man2html?2+bind">bind</A></B>(2).
|
|
|
|
In addition, the following errors may occur:
|
|
<DL COMPACT>
|
|
<DT id="1"><B>EACCES</B>
|
|
|
|
<DD>
|
|
The calling process was not privileged
|
|
(on Linux: the calling process did not have the
|
|
<B>CAP_NET_BIND_SERVICE</B>
|
|
|
|
capability in the user namespace governing its network namespace).
|
|
<DT id="2"><B>EADDRINUSE</B>
|
|
|
|
<DD>
|
|
All privileged ports are in use.
|
|
<DT id="3"><B>EAFNOSUPPORT</B> (<B>EPFNOSUPPORT</B> in glibc 2.7 and earlier)
|
|
|
|
<DD>
|
|
<I>sin</I>
|
|
|
|
is not NULL and
|
|
<I>sin->sin_family</I>
|
|
|
|
is not
|
|
<B>AF_INET</B>.
|
|
|
|
</DL>
|
|
<A NAME="lbAG"> </A>
|
|
<H2>ATTRIBUTES</H2>
|
|
|
|
For an explanation of the terms used in this section, see
|
|
<B><A HREF="/cgi-bin/man/man2html?7+attributes">attributes</A></B>(7).
|
|
|
|
<TABLE BORDER>
|
|
<TR VALIGN=top><TD><B>Interface</B></TD><TD><B>Attribute</B></TD><TD><B>Value</B><BR></TD></TR>
|
|
<TR VALIGN=top><TD>
|
|
<B>bindresvport</B>()
|
|
|
|
</TD><TD>Thread safety</TD><TD>
|
|
glibc >= 2.17: MT-Safe
|
|
|
|
<BR>
|
|
|
|
glibc < 2.17: MT-Unsafe
|
|
<BR></TD></TR>
|
|
</TABLE>
|
|
|
|
<P>
|
|
|
|
The
|
|
<B>bindresvport</B>()
|
|
|
|
function uses a static variable that was not protected by a lock
|
|
before glibc 2.17, rendering the function MT-Unsafe.
|
|
<A NAME="lbAH"> </A>
|
|
<H2>CONFORMING TO</H2>
|
|
|
|
Not in POSIX.1.
|
|
Present on the BSDs, Solaris, and many other systems.
|
|
<A NAME="lbAI"> </A>
|
|
<H2>NOTES</H2>
|
|
|
|
Unlike some
|
|
<B>bindresvport</B>()
|
|
|
|
implementations,
|
|
the glibc implementation ignores any value that the caller supplies in
|
|
<I>sin->sin_port</I>.
|
|
|
|
<A NAME="lbAJ"> </A>
|
|
<H2>SEE ALSO</H2>
|
|
|
|
<B><A HREF="/cgi-bin/man/man2html?2+bind">bind</A></B>(2),
|
|
|
|
<B><A HREF="/cgi-bin/man/man2html?2+getsockname">getsockname</A></B>(2)
|
|
|
|
<A NAME="lbAK"> </A>
|
|
<H2>COLOPHON</H2>
|
|
|
|
This page is part of release 5.05 of the Linux
|
|
<I>man-pages</I>
|
|
|
|
project.
|
|
A description of the project,
|
|
information about reporting bugs,
|
|
and the latest version of this page,
|
|
can be found at
|
|
<A HREF="https://www.kernel.org/doc/man-pages/.">https://www.kernel.org/doc/man-pages/.</A>
|
|
<P>
|
|
|
|
<HR>
|
|
<A NAME="index"> </A><H2>Index</H2>
|
|
<DL>
|
|
<DT id="4"><A HREF="#lbAB">NAME</A><DD>
|
|
<DT id="5"><A HREF="#lbAC">SYNOPSIS</A><DD>
|
|
<DT id="6"><A HREF="#lbAD">DESCRIPTION</A><DD>
|
|
<DT id="7"><A HREF="#lbAE">RETURN VALUE</A><DD>
|
|
<DT id="8"><A HREF="#lbAF">ERRORS</A><DD>
|
|
<DT id="9"><A HREF="#lbAG">ATTRIBUTES</A><DD>
|
|
<DT id="10"><A HREF="#lbAH">CONFORMING TO</A><DD>
|
|
<DT id="11"><A HREF="#lbAI">NOTES</A><DD>
|
|
<DT id="12"><A HREF="#lbAJ">SEE ALSO</A><DD>
|
|
<DT id="13"><A HREF="#lbAK">COLOPHON</A><DD>
|
|
</DL>
|
|
<HR>
|
|
This document was created by
|
|
<A HREF="/cgi-bin/man/man2html">man2html</A>,
|
|
using the manual pages.<BR>
|
|
Time: 00:05:36 GMT, March 31, 2021
|
|
</BODY>
|
|
</HTML>
|