man3/getloadavg.3

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.\"     @(#)getloadavg.3	8.1 (Berkeley) 6/4/93
.\"
.\" 2007-12-08, mtk, Converted from mdoc to man macros
.\"
.TH GETLOADAVG 3 2016-03-15 "Linux" "Linux Programmer's Manual"
.SH NAME
getloadavg \- get system load averages
.SH SYNOPSIS
.nf
.B #include <stdlib.h>
.PP
.BI "int getloadavg(double " loadavg[] ", int " nelem );
.fi
.PP
.in -4n
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.in
.PP
.BR getloadavg ():
.nf
    Since glibc 2.19:
        _DEFAULT_SOURCE
    In glibc up to and including 2.19:
        _BSD_SOURCE
.fi
.SH DESCRIPTION
The
.BR getloadavg ()
function returns the number of processes in the system run queue
averaged over various periods of time.
Up to
.I nelem
samples are retrieved and assigned to successive elements of
.IR loadavg [].
The system imposes a maximum of 3 samples, representing averages
over the last 1, 5, and 15 minutes, respectively.
.SH RETURN VALUE
If the load average was unobtainable, \-1 is returned; otherwise,
the number of samples actually retrieved is returned.
.\" .SH HISTORY
.\" The
.\" BR getloadavg ()
.\" function appeared in
.\" 4.3BSD Reno .
.SH VERSIONS
This function is available in glibc since version 2.2.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lb lb lb
l l l.
Interface	Attribute	Value
T{
.BR getloadavg ()
T}	Thread safety	MT-Safe
.TE
.SH CONFORMING TO
Not in POSIX.1.
Present on the BSDs and Solaris.
.\" mdoc seems to have a bug - there must be no newline here
.SH SEE ALSO
.BR uptime (1),
.BR proc (5)