xref: /trueos/lib/libc/sys/mincore.2 (revision b7cbd895d180129e2f1712f7ac2d6a6006080536)
1.\" Copyright (c) 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.\" 4. 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.\"	@(#)mincore.2	8.1 (Berkeley) 6/9/93
29.\" $FreeBSD$
30.\"
31.Dd January 17, 2003
32.Dt MINCORE 2
33.Os
34.Sh NAME
35.Nm mincore
36.Nd determine residency of memory pages
37.Sh LIBRARY
38.Lb libc
39.Sh SYNOPSIS
40.In sys/mman.h
41.Ft int
42.Fn mincore "const void *addr" "size_t len" "char *vec"
43.Sh DESCRIPTION
44The
45.Fn mincore
46system call determines whether each of the pages in the region beginning at
47.Fa addr
48and continuing for
49.Fa len
50bytes is resident.
51.\"The beginning address,
52.\".Fa addr ,
53.\"is first rounded down to a multiple of the page size (see
54.\".Xr getpagesize 3 ) .
55.\"The end address,
56.\".Fa addr No + Fa len ,
57.\"is rounded up to a multiple of the page size.
58The status is returned in the
59.Fa vec
60array, one character per page.
61Each character is either 0 if the page is not resident, or a combination of
62the following flags (defined in
63.In sys/mman.h ) :
64.Bl -tag -width ".Dv MINCORE_REFERENCED_OTHER"
65.It Dv MINCORE_INCORE
66Page is in core (resident).
67.It Dv MINCORE_REFERENCED
68Page has been referenced by us.
69.It Dv MINCORE_MODIFIED
70Page has been modified by us.
71.It Dv MINCORE_REFERENCED_OTHER
72Page has been referenced.
73.It Dv MINCORE_MODIFIED_OTHER
74Page has been modified.
75.It Dv MINCORE_SUPER
76Page is part of a "super" page. (only i386 & amd64)
77.El
78.Pp
79The information returned by
80.Fn mincore
81may be out of date by the time the system call returns.
82The only way to ensure that a page is resident is to lock it into memory
83with the
84.Xr mlock 2
85system call.
86.Sh RETURN VALUES
87.Rv -std mincore
88.Sh ERRORS
89The
90.Fn mincore
91system call will fail if:
92.Bl -tag -width Er
93.It Bq Er ENOMEM
94The virtual address range specified by the
95.Fa addr
96and
97.Fa len
98arguments is not fully mapped.
99.It Bq Er EFAULT
100The
101.Fa vec
102argument points to an illegal address.
103.El
104.Sh SEE ALSO
105.Xr madvise 2 ,
106.Xr mlock 2 ,
107.Xr mprotect 2 ,
108.Xr msync 2 ,
109.Xr munmap 2 ,
110.Xr getpagesize 3
111.Sh HISTORY
112The
113.Fn mincore
114system call first appeared in
115.Bx 4.4 .
116