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A
ATOMIC_*_LOCK_FREE
Macros that indicate whether an atomic type is lock-free (C11)

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        Macros that indicate whether an atomic type is lock-free (C11)
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        Data types for atomic operations (C11)
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        Safely add to a variable (QNX OS)
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        Safely clear bits in a variable (QNX OS)
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        Safely clear bits in a variable, returning the previous value (QNX OS)
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        Generic memory order-dependent fence synchronization primitive (C11)
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        Safely toggle bits in a variable, returning the previous value (QNX OS)
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        A pointer to a vector of auxiliary arguments to main()
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ATOMIC_*_LOCK_FREE

QNX SDP8.0C Library ReferenceAPIDeveloper

Macros that indicate whether an atomic type is lock-free (C11)

Synopsis:

#include <stdatomic.h>

#define ATOMIC_BOOL_LOCK_FREE ...
#define ATOMIC_CHAR_LOCK_FREE ...
#define ATOMIC_CHAR16_T_LOCK_FREE ...
#define ATOMIC_CHAR32_T_LOCK_FREE ...
#define ATOMIC_WCHAR_T_LOCK_FREE ...
#define ATOMIC_SHORT_LOCK_FREE ...
#define ATOMIC_INT_LOCK_FREE ...
#define ATOMIC_LONG_LOCK_FREE ...
#define ATOMIC_LLONG_LOCK_FREE ...
#define ATOMIC_POINTER_LOCK_FREE ...

Description:

The ATOMIC_*_LOCK_FREE macros expand to preprocessor constant expressions that indicate whether the associated atomic types (see the atomic_* types) are lock-free:


Value	Meaning
0	The atomic type is never lock-free.
1	The atomic type is sometimes lock-free.
2	The atomic type is always lock-free.

This depends on your target platform; if the compiler can't generate lock-free instructions for your target, you need to link your program against libatomic.

The implementation of atomic functions may depend on the architecture. For more information, see LL/SC vs LSE atomic operations in the description in Building Embedded Systems of the cpuinfo area of the system page.

Classification:

Page updated: August 09, 2024