# Manual browser: atomic_or(3)

ATOMIC_OR(3) | Library Functions Manual | ATOMIC_OR(3) |

# NAME

**atomic_or**,

**atomic_or_32**,

**atomic_or_uint**,

**atomic_or_ulong**,

**atomic_or_64**,

**atomic_or_32_nv**,

**atomic_or_uint_nv**,

**atomic_or_ulong_nv**,

**atomic_or_64_nv**— atomic logical ‘or’ operations

# SYNOPSIS

**#include <sys/atomic.h>**

*void*

**atomic_or_32**(*volatile uint32_t *ptr*, *uint32_t bits*);

*void*

**atomic_or_uint**(*volatile unsigned int *ptr*, *unsigned int bits*);

*void*

**atomic_or_ulong**(*volatile unsigned long *ptr*, *unsigned long bits*);

*void*

**atomic_or_64**(*volatile uint64_t *ptr*, *uint64_t bits*);

*uint32_t*

**atomic_or_32_nv**(*volatile uint32_t *ptr*, *uint32_t bits*);

*unsigned int*

**atomic_or_uint_nv**(*volatile unsigned int *ptr*, *unsigned int bits*);

*unsigned long*

**atomic_or_ulong_nv**(*volatile unsigned long *ptr*, *unsigned long bits*);

*uint64_t*

**atomic_or_64_nv**(*volatile uint64_t *ptr*, *uint64_t bits*);

# DESCRIPTION

The**atomic_or**family of functions load the value of the variable referenced by

*ptr*, perform a logical ‘or’ with the value

*bits*, and store the result back to the variable referenced by

*ptr*in an atomic fashion.

The ***_nv**() variants of these functions return the new value.

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_or**functions first appeared in NetBSD 5.0.

April 11, 2007 | NetBSD 7.0 |