.\" $OpenBSD: atomic_load_int.9,v 1.1 2022/03/10 14:12:40 bluhm Exp $
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.\" Copyright (c) 2014 David Gwynne <dlg@openbsd.org>
.\" Copyright (c) 2022 Alexander Bluhm <bluhm@openbsd.org>
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.Dd $Mdocdate: March 10 2022 $
.Dt ATOMIC_LOAD_INT 9
.Os
.Sh NAME
.Nm atomic_load_int ,
.Nm atomic_load_long ,
.Nm atomic_store_long ,
.Nm atomic_store_int
.Nd atomic read and write memory operations
.Sh SYNOPSIS
.In sys/atomic.h
.Ft unsigned int
.Fn atomic_load_int "volatile unsigned int *p"
.Ft unsigned long
.Fn atomic_load_long "volatile unsigned long *p"
.Ft void
.Fn atomic_store_int "volatile unsigned int *p" "unsigned int v"
.Ft void
.Fn atomic_store_long "volatile unsigned long *p" "unsigned long v"
.Sh DESCRIPTION
The atomic_load and atomic_store set of functions provide an interface
for atomically performing read or write memory operations with
respect to interrupts and multiple processors in the system.
.Pp
The atomic_store functions change the value referenced by the pointer
.Fa p
to the value
.Fa v .
.Sh CONTEXT
.Fn atomic_load_int ,
.Fn atomic_load_long ,
.Fn atomic_store_int ,
and
.Fn atomic_store_long
can all be called during autoconf, from process context, or from
interrupt context.
.Sh RETURN VALUES
.Nm atomic_load_int
and
.Nm atomic_load_long
return the value at
.Fa p .
.Sh SEE ALSO
.Xr atomic_add_int 9 ,
.Xr atomic_add_long 9 ,
.Xr atomic_sub_int 9 ,
.Xr atomic_sub_long 9
.Sh HISTORY
The atomic_load and atomic_store functions first appeared in
.Ox 7.1 .