1.\" Copyright (c) 1985, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)getrusage.2 8.1 (Berkeley) 6/4/93 29.\" $FreeBSD: src/lib/libc/sys/getrusage.2,v 1.10.2.5 2001/12/14 18:34:00 ru Exp $ 30.\" $DragonFly: src/lib/libc/sys/getrusage.2,v 1.3 2006/02/17 19:35:06 swildner Exp $ 31.\" 32.Dd June 4, 1993 33.Dt GETRUSAGE 2 34.Os 35.Sh NAME 36.Nm getrusage 37.Nd get information about resource utilization 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In sys/types.h 42.In sys/time.h 43.In sys/resource.h 44.Fd "#define RUSAGE_SELF 0" 45.Fd "#define RUSAGE_CHILDREN -1" 46.Ft int 47.Fn getrusage "int who" "struct rusage *rusage" 48.Sh DESCRIPTION 49.Fn Getrusage 50returns information describing the resources utilized by the current 51process, or all its terminated child processes. 52The 53.Fa who 54parameter is either 55.Dv RUSAGE_SELF 56or 57.Dv RUSAGE_CHILDREN . 58The buffer to which 59.Fa rusage 60points will be filled in with 61the following structure: 62.Bd -literal 63struct rusage { 64 struct timeval ru_utime; /* user time used */ 65 struct timeval ru_stime; /* system time used */ 66 long ru_maxrss; /* max resident set size */ 67 long ru_ixrss; /* integral shared text memory size */ 68 long ru_idrss; /* integral unshared data size */ 69 long ru_isrss; /* integral unshared stack size */ 70 long ru_minflt; /* page reclaims */ 71 long ru_majflt; /* page faults */ 72 long ru_nswap; /* swaps */ 73 long ru_inblock; /* block input operations */ 74 long ru_oublock; /* block output operations */ 75 long ru_msgsnd; /* messages sent */ 76 long ru_msgrcv; /* messages received */ 77 long ru_nsignals; /* signals received */ 78 long ru_nvcsw; /* voluntary context switches */ 79 long ru_nivcsw; /* involuntary context switches */ 80}; 81.Ed 82.Pp 83The fields are interpreted as follows: 84.Bl -tag -width ru_minfltaa 85.It Fa ru_utime 86the total amount of time spent executing in user mode. 87.It Fa ru_stime 88the total amount of time spent in the system executing on behalf 89of the process(es). 90.It Fa ru_maxrss 91the maximum resident set size utilized (in kilobytes). 92.It Fa ru_ixrss 93an 94.Dq integral 95value indicating the amount of memory used 96by the text segment 97that was also shared among other processes. This value is expressed 98in units of kilobytes * ticks-of-execution. 99Ticks are statistics clock ticks. 100The statistics clock has a frequency of 101.Fn sysconf _SC_CLOCK_TCK 102ticks per second. 103.It Fa ru_idrss 104an integral value of the amount of unshared memory residing in the 105data segment of a process (expressed in units of 106kilobytes * ticks-of-execution). 107.It Fa ru_isrss 108an integral value of the amount of unshared memory residing in the 109stack segment of a process (expressed in units of 110kilobytes * ticks-of-execution). 111.It Fa ru_minflt 112the number of page faults serviced without any I/O activity; here 113I/O activity is avoided by 114.Dq reclaiming 115a page frame from 116the list of pages awaiting reallocation. 117.It Fa ru_majflt 118the number of page faults serviced that required I/O activity. 119.It Fa ru_nswap 120the number of times a process was 121.Dq swapped 122out of main 123memory. 124.It Fa ru_inblock 125the number of times the file system had to perform input. 126.It Fa ru_oublock 127the number of times the file system had to perform output. 128.It Fa ru_msgsnd 129the number of IPC messages sent. 130.It Fa ru_msgrcv 131the number of IPC messages received. 132.It Fa ru_nsignals 133the number of signals delivered. 134.It Fa ru_nvcsw 135the number of times a context switch resulted due to a process 136voluntarily giving up the processor before its time slice was 137completed (usually to await availability of a resource). 138.It Fa ru_nivcsw 139the number of times a context switch resulted due to a higher 140priority process becoming runnable or because the current process 141exceeded its time slice. 142.El 143.Sh NOTES 144The numbers 145.Fa ru_inblock 146and 147.Fa ru_oublock 148account only for real 149I/O; data supplied by the caching mechanism is charged only 150to the first process to read or write the data. 151.Sh RETURN VALUES 152.Rv -std getrusage 153.Sh ERRORS 154The 155.Fn getrusage 156function will fail if: 157.Bl -tag -width Er 158.It Bq Er EINVAL 159The 160.Fa who 161parameter is not a valid value. 162.It Bq Er EFAULT 163The address specified by the 164.Fa rusage 165parameter is not in a valid part of the process address space. 166.El 167.Sh SEE ALSO 168.Xr gettimeofday 2 , 169.Xr wait 2 , 170.Xr clocks 7 171.Sh HISTORY 172The 173.Fn getrusage 174function call appeared in 175.Bx 4.2 . 176.Sh BUGS 177There is no way to obtain information about a child process 178that has not yet terminated. 179