1.\" $OpenBSD: getrusage.2,v 1.13 2007/05/31 19:19:32 jmc Exp $ 2.\" 3.\" Copyright (c) 1985, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)getrusage.2 8.1 (Berkeley) 6/4/93 31.\" 32.Dd $Mdocdate: May 31 2007 $ 33.Dt GETRUSAGE 2 34.Os 35.Sh NAME 36.Nm getrusage 37.Nd get information about resource utilization 38.Sh SYNOPSIS 39.Fd #include <sys/time.h> 40.Fd #include <sys/resource.h> 41.Pp 42.Fd #define RUSAGE_SELF 0 43.Fd #define RUSAGE_CHILDREN -1 44.Ft int 45.Fn getrusage "int who" "struct rusage *rusage" 46.Sh DESCRIPTION 47.Fn getrusage 48returns information describing the resources utilized by the current 49process, or all its terminated child processes. 50The 51.Fa who 52parameter is either 53.Dv RUSAGE_SELF 54or 55.Dv RUSAGE_CHILDREN . 56The buffer to which 57.Fa rusage 58points will be filled in with 59the following structure: 60.Bd -literal 61struct rusage { 62 struct timeval ru_utime; /* user time used */ 63 struct timeval ru_stime; /* system time used */ 64 long ru_maxrss; /* max resident set size */ 65 long ru_ixrss; /* integral shared text memory size */ 66 long ru_idrss; /* integral unshared data size */ 67 long ru_isrss; /* integral unshared stack size */ 68 long ru_minflt; /* page reclaims */ 69 long ru_majflt; /* page faults */ 70 long ru_nswap; /* swaps */ 71 long ru_inblock; /* block input operations */ 72 long ru_oublock; /* block output operations */ 73 long ru_msgsnd; /* messages sent */ 74 long ru_msgrcv; /* messages received */ 75 long ru_nsignals; /* signals received */ 76 long ru_nvcsw; /* voluntary context switches */ 77 long ru_nivcsw; /* involuntary context switches */ 78}; 79.Ed 80.Pp 81The fields are interpreted as follows: 82.Bl -tag -width ru_minfltaa 83.It Fa ru_utime 84the total amount of time spent executing in user mode. 85.It Fa ru_stime 86the total amount of time spent in the system executing on behalf 87of the process(es). 88.It Fa ru_maxrss 89the maximum resident set size utilized (in kilobytes). 90.It Fa ru_ixrss 91an \*(lqintegral\*(rq value indicating the amount of memory used 92by the text segment 93that was also shared among other processes. 94This value is expressed in units of kilobytes * ticks-of-execution. 95.It Fa ru_idrss 96an integral value of the amount of unshared memory residing in the 97data segment of a process (expressed in units of 98kilobytes * ticks-of-execution). 99.It Fa ru_isrss 100an integral value of the amount of unshared memory residing in the 101stack segment of a process (expressed in units of 102kilobytes * ticks-of-execution). 103.It Fa ru_minflt 104the number of page faults serviced without any I/O activity; here 105I/O activity is avoided by \*(lqreclaiming\*(rq a page frame from 106the list of pages awaiting reallocation. 107.It Fa ru_majflt 108the number of page faults serviced that required I/O activity. 109.It Fa ru_nswap 110the number of times a process was \*(lqswapped\*(rq out of main 111memory. 112.It Fa ru_inblock 113the number of times the file system had to perform input. 114.It Fa ru_oublock 115the number of times the file system had to perform output. 116.It Fa ru_msgsnd 117the number of IPC messages sent. 118.It Fa ru_msgrcv 119the number of IPC messages received. 120.It Fa ru_nsignals 121the number of signals delivered. 122.It Fa ru_nvcsw 123the number of times a context switch resulted due to a process 124voluntarily giving up the processor before its time slice was 125completed (usually to await availability of a resource). 126.It Fa ru_nivcsw 127the number of times a context switch resulted due to a higher 128priority process becoming runnable or because the current process 129exceeded its time slice. 130.El 131.Sh NOTES 132The numbers 133.Fa ru_inblock 134and 135.Fa ru_oublock 136account only for real 137I/O; data supplied by the caching mechanism is charged only 138to the first process to read or write the data. 139.Sh RETURN VALUES 140Upon success, a value of zero is returned. 141Otherwise, \-1 is returned and 142.Va errno 143is set to indicate the error. 144.Sh ERRORS 145.Fn getrusage 146will fail if: 147.Bl -tag -width Er 148.It Bq Er EINVAL 149The 150.Fa who 151parameter is not a valid value. 152.It Bq Er EFAULT 153The address specified by the 154.Fa rusage 155parameter is not in a valid part of the process address space. 156.El 157.Sh SEE ALSO 158.Xr clock_gettime 2 , 159.Xr gettimeofday 2 , 160.Xr wait 2 161.Sh HISTORY 162The 163.Fn getrusage 164function call appeared in 165.Bx 4.2 . 166.Sh BUGS 167There is no way to obtain information about a child process 168that has not yet terminated. 169