NAME
atomic_swap,
atomic_swap_32,
atomic_swap_uint,
atomic_swap_ulong,
atomic_swap_ptr,
atomic_swap_64 —
atomic swap operations
SYNOPSIS
#include
<sys/atomic.h>
uint32_t
atomic_swap_32(volatile
uint32_t *ptr, uint32_t
new);
unsigned int
atomic_swap_uint(volatile
unsigned int *ptr,
unsigned int new);
unsigned long
atomic_swap_ulong(volatile
unsigned long *ptr,
unsigned long new);
void *
atomic_swap_ptr(volatile
void *ptr, void
*new);
uint64_t
atomic_swap_64(volatile
uint64_t *ptr, uint64_t
new);
DESCRIPTION
Theatomic_swap family of functions perform a swap
operation in an atomic fashion. The value of the variable referenced by
ptr is replaced by new and the old
value returned.
The 64-bit variants of these functions are available only on
platforms that can support atomic 64-bit memory access. Applications can
check for the availability of 64-bit atomic memory operations by testing if
the pre-processor macro __HAVE_ATOMIC64_OPS is
defined.
SEE ALSO
HISTORY
The atomic_swap functions first appeared
in NetBSD 5.0.