.\" Copyright (c) 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" %sccs.include.redist.roff%
.\"
.\"	@(#)madvise.2	8.1 (Berkeley) 06/09/93
.\"
.Dd 
.Dt MADVISE 2
.Os
.Sh NAME
.Nm madvise
.Nd give advise about use of memory
.Sh SYNOPSIS
.Fn madvise "caddr_t addr" "int len" "int behav"
.Sh DESCRIPTION
The
.Fn madvise
system call
allows a process that has knowledge of its memory behavior
to describe it to the system.
The known behaviors are given in
.Pa <sys/mman.h> :
.Bd -literal
#define	MADV_NORMAL	0	/* no further special treatment */
#define	MADV_RANDOM	1	/* expect random page references */
#define	MADV_SEQUENTIAL	2	/* expect sequential references */
#define	MADV_WILLNEED	3	/* will need these pages */
#define	MADV_DONTNEED	4	/* don't need these pages */
#define	MADV_SPACEAVAIL	5	/* insure that resources are reserved */
.Ed
.Sh SEE ALSO
.Xr msync 2 ,
.Xr munmap 2 ,
.Xr mprotect 2 ,
.Xr mincore 2
.Sh HISTORY
The
.Nm madvise
function first appeared in 4.4BSD.