1.\" $NetBSD: mincore.2,v 1.19 2004/05/13 10:20:58 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. 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.\" @(#)mincore.2 8.1 (Berkeley) 6/9/93 31.\" 32.Dd June 6, 1999 33.Dt MINCORE 2 34.Os 35.Sh NAME 36.Nm mincore 37.Nd determine residency of memory pages 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In sys/mman.h 42.Ft int 43.Fn mincore "void *addr" "size_t len" "char *vec" 44.Sh DESCRIPTION 45The 46.Fn mincore 47system call 48allows a process to obtain information about whether pages are 49core resident. 50The status of the memory range is returned in the character-per-page array 51.Ar vec . 52If the page is resident, the least significant bit of the corresponding 53character in 54.Ar vec 55will be set. 56Other bits are reserved for additional information 57which future implementations may return. 58.Pp 59Note that the status of each page may change between the call to 60.Fn mincore 61and the return of the page status information. 62In order to guarantee 63that pages will remain in core, the address range must be locked with 64.Xr mlock 2 . 65.Sh RETURN VALUES 66.Fn mincore 67returns 0 on success, or \-1 on failure and sets the variable 68.Va errno 69to indicate the error. 70.Sh ERRORS 71The 72.Fn mincore 73call will fail if: 74.Bl -tag -width Er 75.It Bq Er EFAULT 76.Ar vec 77points to an illegal address. 78.It Bq Er EINVAL 79.Ar addr 80is not a multiple of the system page size. 81.It Bq Er EINVAL 82.Ar len 83is equal to 0. 84.It Bq Er ENOMEM 85The address range specified is invalid for the calling process, 86or one or more of the pages specified in the range are not mapped. 87.El 88.Sh SEE ALSO 89.Xr madvise 2 , 90.Xr mlock 2 , 91.Xr mprotect 2 , 92.Xr msync 2 , 93.Xr munmap 2 , 94.Xr sysconf 3 95.Sh HISTORY 96The 97.Fn mincore 98function first appeared in 99.Bx 4.4 . 100