.\" $OpenBSD: getrusage.2,v 1.5 1999/05/23 14:10:53 aaron Exp $ .\" .\" Copyright (c) 1985, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)getrusage.2 8.1 (Berkeley) 6/4/93 .\" .Dd June 4, 1993 .Dt GETRUSAGE 2 .Os .Sh NAME .Nm getrusage .Nd get information about resource utilization .Sh SYNOPSIS .Fd #include .Fd #include .Fd #define RUSAGE_SELF 0 .Fd #define RUSAGE_CHILDREN -1 .Ft int .Fn getrusage "int who" "struct rusage *rusage" .Sh DESCRIPTION .Fn getrusage returns information describing the resources utilized by the current process, or all its terminated child processes. The .Fa who parameter is either .Dv RUSAGE_SELF or .Dv RUSAGE_CHILDREN . The buffer to which .Fa rusage points will be filled in with the following structure: .Bd -literal struct rusage { struct timeval ru_utime; /* user time used */ struct timeval ru_stime; /* system time used */ long ru_maxrss; /* max resident set size */ long ru_ixrss; /* integral shared text memory size */ long ru_idrss; /* integral unshared data size */ long ru_isrss; /* integral unshared stack size */ long ru_minflt; /* page reclaims */ long ru_majflt; /* page faults */ long ru_nswap; /* swaps */ long ru_inblock; /* block input operations */ long ru_oublock; /* block output operations */ long ru_msgsnd; /* messages sent */ long ru_msgrcv; /* messages received */ long ru_nsignals; /* signals received */ long ru_nvcsw; /* voluntary context switches */ long ru_nivcsw; /* involuntary context switches */ }; .Ed .Pp The fields are interpreted as follows: .Bl -tag -width ru_minfltaa .It Fa ru_utime the total amount of time spent executing in user mode. .It Fa ru_stime the total amount of time spent in the system executing on behalf of the process(es). .It Fa ru_maxrss the maximum resident set size utilized (in kilobytes). .It Fa ru_ixrss an \*(lqintegral\*(rq value indicating the amount of memory used by the text segment that was also shared among other processes. This value is expressed in units of kilobytes * ticks-of-execution. .It Fa ru_idrss an integral value of the amount of unshared memory residing in the data segment of a process (expressed in units of kilobytes * ticks-of-execution). .It Fa ru_isrss an integral value of the amount of unshared memory residing in the stack segment of a process (expressed in units of kilobytes * ticks-of-execution). .It Fa ru_minflt the number of page faults serviced without any I/O activity; here I/O activity is avoided by \*(lqreclaiming\*(rq a page frame from the list of pages awaiting reallocation. .It Fa ru_majflt the number of page faults serviced that required I/O activity. .It Fa ru_nswap the number of times a process was \*(lqswapped\*(rq out of main memory. .It Fa ru_inblock the number of times the file system had to perform input. .It Fa ru_oublock the number of times the file system had to perform output. .It Fa ru_msgsnd the number of IPC messages sent. .It Fa ru_msgrcv the number of IPC messages received. .It Fa ru_nsignals the number of signals delivered. .It Fa ru_nvcsw the number of times a context switch resulted due to a process voluntarily giving up the processor before its time slice was completed (usually to await availability of a resource). .It Fa ru_nivcsw the number of times a context switch resulted due to a higher priority process becoming runnable or because the current process exceeded its time slice. .El .Sh NOTES The numbers .Fa ru_inblock and .Fa ru_oublock account only for real I/O; data supplied by the caching mechanism is charged only to the first process to read or write the data. .Sh ERRORS .Fn getrusage returns -1 on error. The possible errors are: .Bl -tag -width Er .It Bq Er EINVAL The .Fa who parameter is not a valid value. .It Bq Er EFAULT The address specified by the .Fa rusage parameter is not in a valid part of the process address space. .El .Sh SEE ALSO .Xr gettimeofday 2 , .Xr wait 2 .Sh BUGS There is no way to obtain information about a child process that has not yet terminated. .Sh HISTORY The .Fn getrusage function call appeared in .Bx 4.2 .