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<H1>SYSINFO</H1>
Section: Linux Programmer's Manual (2)<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">&nbsp;</A>
<H2>NAME</H2>
sysinfo - return system information
<A NAME="lbAC">&nbsp;</A>
<H2>SYNOPSIS</H2>
<B>#include &lt;<A HREF="file:///usr/include/sys/sysinfo.h">sys/sysinfo.h</A>&gt;</B>
<P>
<B>int sysinfo(struct sysinfo *</B><I>info</I><B>);</B>
<A NAME="lbAD">&nbsp;</A>
<H2>DESCRIPTION</H2>
<B>sysinfo</B>()
returns certain statistics on memory and swap usage,
as well as the load average.
<P>
Until Linux 2.3.16,
<B>sysinfo</B>()
returned information in the following structure:
<P>
struct sysinfo {
<BR>&nbsp;&nbsp;&nbsp;&nbsp;long&nbsp;uptime;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/*&nbsp;Seconds&nbsp;since&nbsp;boot&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;loads[3];&nbsp;&nbsp;/*&nbsp;1,&nbsp;5,&nbsp;and&nbsp;15&nbsp;minute&nbsp;load&nbsp;averages&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;totalram;&nbsp;&nbsp;/*&nbsp;Total&nbsp;usable&nbsp;main&nbsp;memory&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;freeram;&nbsp;&nbsp;&nbsp;/*&nbsp;Available&nbsp;memory&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;sharedram;&nbsp;/*&nbsp;Amount&nbsp;of&nbsp;shared&nbsp;memory&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;bufferram;&nbsp;/*&nbsp;Memory&nbsp;used&nbsp;by&nbsp;buffers&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;totalswap;&nbsp;/*&nbsp;Total&nbsp;swap&nbsp;space&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;freeswap;&nbsp;&nbsp;/*&nbsp;Swap&nbsp;space&nbsp;still&nbsp;available&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;short&nbsp;procs;&nbsp;&nbsp;&nbsp;&nbsp;/*&nbsp;Number&nbsp;of&nbsp;current&nbsp;processes&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;char&nbsp;_f[22];&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/*&nbsp;Pads&nbsp;structure&nbsp;to&nbsp;64&nbsp;bytes&nbsp;*/
};
<P>
In the above structure, the sizes of the memory and swap fields
are given in bytes.
<P>
Since Linux 2.3.23 (i386) and Linux 2.3.48
(all architectures) the structure is:
<P>
struct sysinfo {
<BR>&nbsp;&nbsp;&nbsp;&nbsp;long&nbsp;uptime;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/*&nbsp;Seconds&nbsp;since&nbsp;boot&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;loads[3];&nbsp;&nbsp;/*&nbsp;1,&nbsp;5,&nbsp;and&nbsp;15&nbsp;minute&nbsp;load&nbsp;averages&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;totalram;&nbsp;&nbsp;/*&nbsp;Total&nbsp;usable&nbsp;main&nbsp;memory&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;freeram;&nbsp;&nbsp;&nbsp;/*&nbsp;Available&nbsp;memory&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;sharedram;&nbsp;/*&nbsp;Amount&nbsp;of&nbsp;shared&nbsp;memory&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;bufferram;&nbsp;/*&nbsp;Memory&nbsp;used&nbsp;by&nbsp;buffers&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;totalswap;&nbsp;/*&nbsp;Total&nbsp;swap&nbsp;space&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;freeswap;&nbsp;&nbsp;/*&nbsp;Swap&nbsp;space&nbsp;still&nbsp;available&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;short&nbsp;procs;&nbsp;&nbsp;&nbsp;&nbsp;/*&nbsp;Number&nbsp;of&nbsp;current&nbsp;processes&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;totalhigh;&nbsp;/*&nbsp;Total&nbsp;high&nbsp;memory&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;long&nbsp;freehigh;&nbsp;&nbsp;/*&nbsp;Available&nbsp;high&nbsp;memory&nbsp;size&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;unsigned&nbsp;int&nbsp;mem_unit;&nbsp;&nbsp;&nbsp;/*&nbsp;Memory&nbsp;unit&nbsp;size&nbsp;in&nbsp;bytes&nbsp;*/
<BR>&nbsp;&nbsp;&nbsp;&nbsp;char&nbsp;_f[20-2*sizeof(long)-sizeof(int)];
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;/*&nbsp;Padding&nbsp;to&nbsp;64&nbsp;bytes&nbsp;*/
};
<P>
In the above structure,
sizes of the memory and swap fields are given as multiples of
<I>mem_unit</I>
bytes.
<A NAME="lbAE">&nbsp;</A>
<H2>RETURN VALUE</H2>
On success,
<B>sysinfo</B>()
returns zero.
On error, -1 is returned, and
<I>errno</I>
is set to indicate the cause of the error.
<A NAME="lbAF">&nbsp;</A>
<H2>ERRORS</H2>
<DL COMPACT>
<DT id="1"><B>EFAULT</B>
<DD>
<I>info</I>
is not a valid address.
</DL>
<A NAME="lbAG">&nbsp;</A>
<H2>VERSIONS</H2>
<B>sysinfo</B>()
first appeared in Linux 0.98.pl6.
<A NAME="lbAH">&nbsp;</A>
<H2>CONFORMING TO</H2>
This function is Linux-specific, and should not be used in programs
intended to be portable.
<A NAME="lbAI">&nbsp;</A>
<H2>NOTES</H2>
All of the information provided by this system call is also available via
<I>/proc/meminfo</I>
and
<I>/proc/loadavg</I>.
<A NAME="lbAJ">&nbsp;</A>
<H2>SEE ALSO</H2>
<B><A HREF="/cgi-bin/man/man2html?5+proc">proc</A></B>(5)
<A NAME="lbAK">&nbsp;</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">&nbsp;</A><H2>Index</H2>
<DL>
<DT id="2"><A HREF="#lbAB">NAME</A><DD>
<DT id="3"><A HREF="#lbAC">SYNOPSIS</A><DD>
<DT id="4"><A HREF="#lbAD">DESCRIPTION</A><DD>
<DT id="5"><A HREF="#lbAE">RETURN VALUE</A><DD>
<DT id="6"><A HREF="#lbAF">ERRORS</A><DD>
<DT id="7"><A HREF="#lbAG">VERSIONS</A><DD>
<DT id="8"><A HREF="#lbAH">CONFORMING TO</A><DD>
<DT id="9"><A HREF="#lbAI">NOTES</A><DD>
<DT id="10"><A HREF="#lbAJ">SEE ALSO</A><DD>
<DT id="11"><A HREF="#lbAK">COLOPHON</A><DD>
</DL>
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Time: 00:05:35 GMT, March 31, 2021
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