man3/getloadavg.3

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  30 .\"     @(#)getloadavg.3        8.1 (Berkeley) 6/4/93
  31 .\"
  32 .\" 2007-12-08, mtk, Converted from mdoc to man macros
  33 .\"
  34 .TH GETLOADAVG 3 2016-03-15 "Linux" "Linux Programmer's Manual"
  35 .SH NAME
  36 getloadavg \- get system load averages
  37 .SH SYNOPSIS
  38 .nf
  39 .B #include <stdlib.h>
  40 .PP
  41 .BI "int getloadavg(double " loadavg[] ", int " nelem );
  42 .fi
  43 .PP
  44 .in -4n
  45 Feature Test Macro Requirements for glibc (see
  46 .BR feature_test_macros (7)):
  47 .in
  48 .PP
  49 .BR getloadavg ():
  50 .nf
  51     Since glibc 2.19:
  52         _DEFAULT_SOURCE
  53     In glibc up to and including 2.19:
  54         _BSD_SOURCE
  55 .fi
  56 .SH DESCRIPTION
  57 The
  58 .BR getloadavg ()
  59 function returns the number of processes in the system run queue
  60 averaged over various periods of time.
  61 Up to
  62 .I nelem
  63 samples are retrieved and assigned to successive elements of
  64 .IR loadavg [].
  65 The system imposes a maximum of 3 samples, representing averages
  66 over the last 1, 5, and 15 minutes, respectively.
  67 .SH RETURN VALUE
  68 If the load average was unobtainable, \-1 is returned; otherwise,
  69 the number of samples actually retrieved is returned.
  70 .\" .SH HISTORY
  71 .\" The
  72 .\" BR getloadavg ()
  73 .\" function appeared in
  74 .\" 4.3BSD Reno .
  75 .SH VERSIONS
  76 This function is available in glibc since version 2.2.
  77 .SH ATTRIBUTES
  78 For an explanation of the terms used in this section, see
  79 .BR attributes (7).
  80 .TS
  81 allbox;
  82 lb lb lb
  83 l l l.
  84 Interface       Attribute       Value
  85 T{
  86 .BR getloadavg ()
  87 T}      Thread safety   MT-Safe
  88 .TE
  89 .SH CONFORMING TO
  90 Not in POSIX.1.
  91 Present on the BSDs and Solaris.
  92 .\" mdoc seems to have a bug - there must be no newline here
  93 .SH SEE ALSO
  94 .BR uptime (1),
  95 .BR proc (5)