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Utilities & Libraries
C Library Reference
A
atomic_*
Data types for atomic operations (C11)

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        The arena size for heap allocations
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        Display a diagnostic message and optionally terminate the program
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        Compute the arctangent of an angle
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        Compute the arctangent, determining the quadrant
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        Compute an inverse hyperbolic tangent
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        Register functions to be called during normal program termination
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        Convert a string into a double
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        Convert a string into an integer
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        Convert a string into a long integer
      - ATOMIC_*_LOCK_FREE
        Macros that indicate whether an atomic type is lock-free (C11)
      - atomic_*
        Data types for atomic operations (C11)
      - atomic_add()
        Safely add to a variable (QNX OS)
      - atomic_add_value()
        Safely add to a variable, returning the previous value (QNX OS)
      - atomic_clr()
        Safely clear bits in a variable (QNX OS)
      - atomic_clr_value()
        Safely clear bits in a variable, returning the previous value (QNX OS)
      - atomic_compare_exchange_strong(), atomic_compare_exchange_strong_explicit(), atomic_compare_exchange_weak(), atomic_compare_exchange_weak_explicit()
        Compare and potentially exchange the value of an atomic object (C11)
      - atomic_exchange(), atomic_exchange_explicit()
        Atomically change the value of an atomic object (C11)
      - atomic_fetch_add(), atomic_fetch_add_explicit()
        Atomically add to the value of an atomic object (C11)
      - atomic_fetch_and(), atomic_fetch_and_explicit()
        Atomically AND a value into an atomic object (C11)
      - atomic_fetch_or(), atomic_fetch_or_explicit()
        Atomically OR a value into an atomic object (C11)
      - atomic_fetch_sub(), atomic_fetch_sub_explicit()
        Atomically subtract the value of an atomic object (C11)
      - atomic_fetch_xor(), atomic_fetch_xor_explicit()
        Atomically XOR a value into an atomic object (C11)
      - atomic_flag_clear(), atomic_flag_clear_explicit()
        Atomically clear a flag (C11)
      - atomic_flag_test_and_set(), atomic_flag_test_and_set_explicit()
        Atomically set a flag (C11)
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        Initialize an atomic object (C11)
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        Determine whether atomic operations on an object are lock-free (C11)
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        Atomically read the value of an atomic object (C11)
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        Safely set bits in a variable (QNX OS)
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        Safely set bits in a variable, returning the previous value (QNX OS)
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        Fence between a thread and a signal handler executed in the same thread (C11)
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        Atomically set the value of an atomic object (C11)
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        Safely subtract from a variable (QNX OS)
      - atomic_sub_value()
        Safely subtract from a variable, returning the previous value (QNX OS)
      - atomic_thread_fence()
        Generic memory order-dependent fence synchronization primitive (C11)
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        Safely toggle bits in a variable (QNX OS)
      - atomic_toggle_value()
        Safely toggle bits in a variable, returning the previous value (QNX OS)
      - _auxv
        A pointer to a vector of auxiliary arguments to main()
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atomic_*

QNX SDP8.0C Library ReferenceAPIDeveloper

Data types for atomic operations (C11)

Synopsis:

See below.

Description:

The following data types are defined in <stdatomic.h>:


Typedef name	Full type name
atomic_bool	_Atomic _Bool
atomic_char	_Atomic char
atomic_schar	_Atomic signed char
atomic_uchar	_Atomic unsigned char
atomic_short	_Atomic short
atomic_ushort	_Atomic unsigned short
atomic_int	_Atomic int
atomic_uint	_Atomic unsigned int
atomic_long	_Atomic long
atomic_ulong	_Atomic unsigned long
atomic_llong	_Atomic long long
atomic_ullong	_Atomic unsigned long long
atomic_char16_t	_Atomic char16_t
atomic_char32_t	_Atomic char32_t
atomic_wchar_t	_Atomic wchar
atomic_int_least8_t	_Atomic int_least8_t
atomic_uint_least8_t	_Atomic uint_least8_t
atomic_int_least16_t	_Atomic int_least16_t
atomic_uint_least16_t	_Atomic uint_least16_t
atomic_int_least32_t	_Atomic int_least32_t
atomic_uint_least32_t	_Atomic uint_least32_t
atomic_int_least64_t	_Atomic int_least64_t
atomic_uint_least64_t	_Atomic uint_least64_t
atomic_int_fast8_t	_Atomic int_fast8_t
atomic_uint_fast8_t	_Atomic uint_fast8_t
atomic_int_fast16_t	_Atomic int_fast16_t
atomic_uint_fast16_t	_Atomic uint_fast16_t
atomic_int_fast32_t	_Atomic int_fast32_t
atomic_uint_fast32_t	_Atomic uint_fast32_t
atomic_int_fast64_t	_Atomic int_fast64_t
atomic_uint_fast64_t	_Atomic uint_fast64_t
atomic_intptr_t	_Atomic intptr_t
atomic_uintptr_t	_Atomic uintptr_t
atomic_size_t	_Atomic size_t
atomic_ptrdiff_t	_Atomic ptrdiff_t
atomic_intmax_t	_Atomic intmax_t
atomic_uintmax_t	_Atomic uintmax_t

Classification:

Page updated: August 11, 2025