1.\" $NetBSD: mincore.2,v 1.15 2002/10/01 18:10:44 wiz Exp $ 2.\" 3.\" Copyright (c) 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. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)mincore.2 8.1 (Berkeley) 6/9/93 35.\" 36.Dd June 6, 1999 37.Dt MINCORE 2 38.Os 39.Sh NAME 40.Nm mincore 41.Nd determine residency of memory pages 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.Fd #include \*[Lt]sys/mman.h\*[Gt] 46.Ft int 47.Fn mincore "void *addr" "size_t len" "char *vec" 48.Sh DESCRIPTION 49The 50.Fn mincore 51system call 52allows a process to obtain information about whether pages are 53core resident. 54The status of the memory range is returned in the character-per-page array 55.Ar vec . 56If the page is resident, the least significant bit of the corresponding 57character in 58.Ar vec 59will be set. 60Other bits are reserved for additional information 61which future implementations may return. 62.Pp 63Note that the status of each page may change between the call to 64.Fn mincore 65and the return of the page status information. 66In order to guarantee 67that pages will remain in core, the address range must be locked with 68.Xr mlock 2 . 69.Sh RETURN VALUES 70.Fn mincore 71returns 0 on success, or -1 on failure and sets the variable 72.Va errno 73to indicate the error. 74.Sh ERRORS 75The 76.Fn mincore 77call will fail if: 78.Bl -tag -width Er 79.It Bq Er EFAULT 80.Ar vec 81points to an illegal address. 82.It Bq Er EINVAL 83.Ar addr 84is not a multiple of the system page size. 85.It Bq Er EINVAL 86.Ar len 87is equal to 0. 88.It Bq Er ENOMEM 89The address range specified is invalid for the calling process, 90or one or more of the pages specified in the range are not mapped. 91.El 92.Sh SEE ALSO 93.Xr madvise 2 , 94.Xr mlock 2 , 95.Xr mprotect 2 , 96.Xr msync 2 , 97.Xr munmap 2 , 98.Xr sysconf 3 99.Sh HISTORY 100The 101.Fn mincore 102function first appeared in 103.Bx 4.4 . 104