atomic_swap(3) - NetBSD Manual Pages

ATOMIC_SWAP(3)          NetBSD Library Functions Manual         ATOMIC_SWAP(3)


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

     The atomic_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

     atomic_ops(3)


HISTORY

     The atomic_swap functions first appeared in NetBSD 5.0.

NetBSD 9.1                      April 11, 2007                      NetBSD 9.1