avr_stdint(3)

🌸 avr_stdint(3) — the avr-libc manual page 🌸

okay bestie, sit down, hydrate, and let me tell you about avr_stdint — this is the avr-libc page for <stdint.h>, and it is genuinely one of the most useful little headers in the whole AVR universe. 💖

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✨ NAME ✨

avr_stdint — the header that gives you integer types with exactly the widths you asked for, no guessing, no vibes-based sizeof, periodt.

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🎀 SYNOPSIS 🎀

💅 Exact-width integer types

Integer types having exactly the specified width. Yes bestie, exactly. No notes.

typedef signed char int8_t
typedef unsigned char uint8_t
typedef signed int int16_t
typedef unsigned int uint16_t
typedef signed long int int32_t
typedef unsigned long int uint32_t
typedef signed long long int int64_t
typedef unsigned long long int uint64_t

🫶 Integer types capable of holding object pointers

These allow you to declare variables of the same size as a pointer. Pointer-shaped integers, it's giving "I contain a memory address" energy.

typedef int16_t intptr_t
typedef uint16_t uintptr_t

✨ Minimum-width integer types

Integer types having at least the specified width. At least, babes. They might be thiccer.

typedef int8_t int_least8_t
typedef uint8_t uint_least8_t
typedef int16_t int_least16_t
typedef uint16_t uint_least16_t
typedef int32_t int_least32_t
typedef uint32_t uint_least32_t
typedef int64_t int_least64_t
typedef uint64_t uint_least64_t

🔥 Fastest minimum-width integer types

Integer types being usually fastest having at least the specified width. Usually fastest — that's the promise, and honestly? She delivers.

typedef int8_t int_fast8_t
typedef uint8_t uint_fast8_t
typedef int16_t int_fast16_t
typedef uint16_t uint_fast16_t
typedef int32_t int_fast32_t
typedef uint32_t uint_fast32_t
typedef int64_t int_fast64_t
typedef uint64_t uint_fast64_t

👑 Greatest-width integer types

Types designating integer data capable of representing any value of any integer type in the corresponding signed or unsigned category. The final boss. The main character. 🌈

typedef int64_t intmax_t
typedef uint64_t uintmax_t

💀 Limits of specified-width integer types

C++ implementations should define these macros only when __STDC_LIMIT_MACROS is defined before <stdint.h> is included

not me reminding you twice about that one, because it shows up again later and it's a whole thing 💀

#define INT8_MAX   0x7f
#define INT8_MIN   (-INT8_MAX - 1)
#define UINT8_MAX   (INT8_MAX * 2 + 1)
#define INT16_MAX   0x7fff
#define INT16_MIN   (-INT16_MAX - 1)
#define UINT16_MAX   (__CONCAT(INT16_MAX, U) * 2U + 1U)
#define INT32_MAX   0x7fffffffL
#define INT32_MIN   (-INT32_MAX - 1L)
#define UINT32_MAX   (__CONCAT(INT32_MAX, U) * 2UL + 1UL)
#define INT64_MAX   0x7fffffffffffffffLL
#define INT64_MIN   (-INT64_MAX - 1LL)
#define UINT64_MAX   (__CONCAT(INT64_MAX, U) * 2ULL + 1ULL)

🦋 Limits of minimum-width integer types

#define INT_LEAST8_MAX   INT8_MAX
#define INT_LEAST8_MIN   INT8_MIN
#define UINT_LEAST8_MAX   UINT8_MAX
#define INT_LEAST16_MAX   INT16_MAX
#define INT_LEAST16_MIN   INT16_MIN
#define UINT_LEAST16_MAX   UINT16_MAX
#define INT_LEAST32_MAX   INT32_MAX
#define INT_LEAST32_MIN   INT32_MIN
#define UINT_LEAST32_MAX   UINT32_MAX
#define INT_LEAST64_MAX   INT64_MAX
#define INT_LEAST64_MIN   INT64_MIN
#define UINT_LEAST64_MAX   UINT64_MAX

⭐ Limits of fastest minimum-width integer types

#define INT_FAST8_MAX   INT8_MAX
#define INT_FAST8_MIN   INT8_MIN
#define UINT_FAST8_MAX   UINT8_MAX
#define INT_FAST16_MAX   INT16_MAX
#define INT_FAST16_MIN   INT16_MIN
#define UINT_FAST16_MAX   UINT16_MAX
#define INT_FAST32_MAX   INT32_MAX
#define INT_FAST32_MIN   INT32_MIN
#define UINT_FAST32_MAX   UINT32_MAX
#define INT_FAST64_MAX   INT64_MAX
#define INT_FAST64_MIN   INT64_MIN
#define UINT_FAST64_MAX   UINT64_MAX

🧚 Limits of integer types capable of holding object pointers

#define INTPTR_MAX   INT16_MAX
#define INTPTR_MIN   INT16_MIN
#define UINTPTR_MAX   UINT16_MAX

💜 Limits of greatest-width integer types

#define INTMAX_MAX   INT64_MAX
#define INTMAX_MIN   INT64_MIN
#define UINTMAX_MAX   UINT64_MAX

🌸 Limits of other integer types

C++ implementations should define these macros only when __STDC_LIMIT_MACROS is defined before <stdint.h> is included

told you it was coming back 🙈

#define PTRDIFF_MAX   INT16_MAX
#define PTRDIFF_MIN   INT16_MIN
#define SIG_ATOMIC_MAX   INT8_MAX
#define SIG_ATOMIC_MIN   INT8_MIN
#define SIZE_MAX   UINT16_MAX
#define WCHAR_MAX   __WCHAR_MAX__
#define WCHAR_MIN   __WCHAR_MIN__
#define WINT_MAX   __WINT_MAX__
#define WINT_MIN   __WINT_MIN__

🍓 Macros for integer constants

C++ implementations should define these macros only when __STDC_CONSTANT_MACROS is defined before <stdint.h> is included.

These definitions are valid for integer constants without suffix and for macros defined as integer constant without suffix. Read that twice bestie, it's doing a lot of work in one sentence. 😌

#define INT8_C(value)   ((int8_t) value)
#define UINT8_C(value)   ((uint8_t) __CONCAT(value, U))
#define INT16_C(value)   value
#define UINT16_C(value)   __CONCAT(value, U)
#define INT32_C(value)   __CONCAT(value, L)
#define UINT32_C(value)   __CONCAT(value, UL)
#define INT64_C(value)   __CONCAT(value, LL)
#define UINT64_C(value)   __CONCAT(value, ULL)
#define INTMAX_C(value)   __CONCAT(value, LL)
#define UINTMAX_C(value)   __CONCAT(value, ULL)

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💖 Detailed Description 💖

#include <stdint.h>

Use [u]intN_t if you need exactly N bits. That's the whole vibe check.

Since these typedefs are mandated by the C99 standard, they are preferred over rolling your own typedefs. ngl, stop writing your own typedef unsigned char byte; — the standard already did it, and hers ate. 💅

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📚 Macro Definition Documentation 📚

okay this is the big one, we're going alphabetically-ish, buckle up 🎀

#define INT16_C(value) value

define a constant of type int16_t

#define INT16_MAX 0x7fff

largest positive value an int16_t can hold.

#define INT16_MIN (-INT16_MAX - 1)

smallest negative value an int16_t can hold.

#define INT32_C(value) __CONCAT(value, L)

define a constant of type int32_t

#define INT32_MAX 0x7fffffffL

largest positive value an int32_t can hold.

#define INT32_MIN (-INT32_MAX - 1L)

smallest negative value an int32_t can hold.

#define INT64_C(value) __CONCAT(value, LL)

define a constant of type int64_t

#define INT64_MAX 0x7fffffffffffffffLL

largest positive value an int64_t can hold.

#define INT64_MIN (-INT64_MAX - 1LL)

smallest negative value an int64_t can hold.

#define INT8_C(value) ((int8_t) value)

define a constant of type int8_t

#define INT8_MAX 0x7f

largest positive value an int8_t can hold.

#define INT8_MIN (-INT8_MAX - 1)

smallest negative value an int8_t can hold.

#define INT_FAST16_MAX INT16_MAX

largest positive value an int_fast16_t can hold.

#define INT_FAST16_MIN INT16_MIN

smallest negative value an int_fast16_t can hold.

#define INT_FAST32_MAX INT32_MAX

largest positive value an int_fast32_t can hold.

#define INT_FAST32_MIN INT32_MIN

smallest negative value an int_fast32_t can hold.

#define INT_FAST64_MAX INT64_MAX

largest positive value an int_fast64_t can hold.

#define INT_FAST64_MIN INT64_MIN

smallest negative value an int_fast64_t can hold.

#define INT_FAST8_MAX INT8_MAX

largest positive value an int_fast8_t can hold.

#define INT_FAST8_MIN INT8_MIN

smallest negative value an int_fast8_t can hold.

#define INT_LEAST16_MAX INT16_MAX

largest positive value an int_least16_t can hold.

#define INT_LEAST16_MIN INT16_MIN

smallest negative value an int_least16_t can hold.

#define INT_LEAST32_MAX INT32_MAX

largest positive value an int_least32_t can hold.

#define INT_LEAST32_MIN INT32_MIN

smallest negative value an int_least32_t can hold.

#define INT_LEAST64_MAX INT64_MAX

largest positive value an int_least64_t can hold.

#define INT_LEAST64_MIN INT64_MIN

smallest negative value an int_least64_t can hold.

#define INT_LEAST8_MAX INT8_MAX

largest positive value an int_least8_t can hold.

#define INT_LEAST8_MIN INT8_MIN

smallest negative value an int_least8_t can hold.

#define INTMAX_C(value) __CONCAT(value, LL)

define a constant of type intmax_t

#define INTMAX_MAX INT64_MAX

largest positive value an intmax_t can hold.

#define INTMAX_MIN INT64_MIN

smallest negative value an intmax_t can hold.

#define INTPTR_MAX INT16_MAX

largest positive value an intptr_t can hold.

#define INTPTR_MIN INT16_MIN

smallest negative value an intptr_t can hold.

#define PTRDIFF_MAX INT16_MAX

largest positive value a ptrdiff_t can hold.

#define PTRDIFF_MIN INT16_MIN

smallest negative value a ptrdiff_t can hold.

#define SIG_ATOMIC_MAX INT8_MAX

largest positive value a sig_atomic_t can hold.

#define SIG_ATOMIC_MIN INT8_MIN

smallest negative value a sig_atomic_t can hold.

#define SIZE_MAX UINT16_MAX

largest value a size_t can hold.

#define UINT16_C(value) __CONCAT(value, U)

define a constant of type uint16_t

#define UINT16_MAX (__CONCAT(INT16_MAX, U) * 2U + 1U)

largest value an uint16_t can hold.

#define UINT32_C(value) __CONCAT(value, UL)

define a constant of type uint32_t

#define UINT32_MAX (__CONCAT(INT32_MAX, U) * 2UL + 1UL)

largest value an uint32_t can hold.

#define UINT64_C(value) __CONCAT(value, ULL)

define a constant of type uint64_t

#define UINT64_MAX (__CONCAT(INT64_MAX, U) * 2ULL + 1ULL)

largest value an uint64_t can hold.

#define UINT8_C(value) ((uint8_t) __CONCAT(value, U))

define a constant of type uint8_t

#define UINT8_MAX (INT8_MAX * 2 + 1)

largest value an uint8_t can hold.

#define UINT_FAST16_MAX UINT16_MAX

largest value an uint_fast16_t can hold.

#define UINT_FAST32_MAX UINT32_MAX

largest value an uint_fast32_t can hold.

#define UINT_FAST64_MAX UINT64_MAX

largest value an uint_fast64_t can hold.

#define UINT_FAST8_MAX UINT8_MAX

largest value an uint_fast8_t can hold.

#define UINT_LEAST16_MAX UINT16_MAX

largest value an uint_least16_t can hold.

#define UINT_LEAST32_MAX UINT32_MAX

largest value an uint_least32_t can hold.

#define UINT_LEAST64_MAX UINT64_MAX

largest value an uint_least64_t can hold.

#define UINT_LEAST8_MAX UINT8_MAX

largest value an uint_least8_t can hold.

#define UINTMAX_C(value) __CONCAT(value, ULL)

define a constant of type uintmax_t

#define UINTMAX_MAX UINT64_MAX

largest value an uintmax_t can hold.

#define UINTPTR_MAX UINT16_MAX

largest value an uintptr_t can hold.

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and that's only part 1 bestie, there's more where that came from 🌈💖

💖 Typedef Documentation 💖

okay bestie, we made it to the typedefs. this is where avr-libc gives all the integer types their little nicknames so you don't have to write signed long long int every single time like a Victorian ghost. 👻✨ every single typedef is below, no skips, no cap. 💅

• typedef signed int int16_t — a 16-bit signed type. 🩷
• typedef signed long int int32_t — a 32-bit signed type. 💜
• typedef signed long long int int64_t — a 64-bit signed type. 🔥
  • 🚨 Note: this type is not available when the compiler option -mint8 is in effect. 😭
• typedef signed char int8_t — an 8-bit signed type. 🍓
• typedef int16_t int_fast16_t — fastest signed int with at least 16 bits. ⚡
• typedef int32_t int_fast32_t — fastest signed int with at least 32 bits. ⚡
• typedef int64_t int_fast64_t — fastest signed int with at least 64 bits. ⚡
  • 🚨 Note: this type is not available when the compiler option -mint8 is in effect. 😭
• typedef int8_t int_fast8_t — fastest signed int with at least 8 bits. ⚡
• typedef int16_t int_least16_t — signed int with at least 16 bits. 🌸
• typedef int32_t int_least32_t — signed int with at least 32 bits. 🌸
• typedef int64_t int_least64_t — signed int with at least 64 bits. 🌸
  • 🚨 Note: this type is not available when the compiler option -mint8 is in effect. 😭
• typedef int8_t int_least8_t — signed int with at least 8 bits. 🌸
• typedef int64_t intmax_t — largest signed int available. 👑
• typedef int16_t intptr_t — signed pointer compatible type. 🫶
• typedef unsigned int uint16_t — a 16-bit unsigned type. ✨
• typedef unsigned long int uint32_t — a 32-bit unsigned type. ✨
• typedef unsigned long long int uint64_t — a 64-bit unsigned type. ✨
  • 🚨 Note: this type is not available when the compiler option -mint8 is in effect. 😭
• typedef unsigned char uint8_t — an 8-bit unsigned type. 🌈
• typedef uint16_t uint_fast16_t — fastest unsigned int with at least 16 bits. ⚡
• typedef uint32_t uint_fast32_t — fastest unsigned int with at least 32 bits. ⚡
• typedef uint64_t uint_fast64_t — fastest unsigned int with at least 64 bits. ⚡
  • 🚨 Note: this type is not available when the compiler option -mint8 is in effect. 😭
• typedef uint8_t uint_fast8_t — fastest unsigned int with at least 8 bits. ⚡
• typedef uint16_t uint_least16_t — unsigned int with at least 16 bits. 🌼
• typedef uint32_t uint_least32_t — unsigned int with at least 32 bits. 🌼
• typedef uint64_t uint_least64_t — unsigned int with at least 64 bits. 🌼
  • 🚨 Note: this type is not available when the compiler option -mint8 is in effect. 😭
• typedef uint8_t uint_least8_t — unsigned int with at least 8 bits. 🌼
• typedef uint64_t uintmax_t — largest unsigned int available. 👑
• typedef uint16_t uintptr_t — unsigned pointer compatible type. 🫶

✍️ Author ✍️

Generated automatically by Doxygen for avr-libc from the source code. 🤖✨ like, the robots wrote this whole thing, and honestly? they ate. 💅

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and that's the whole typedef journey, bestie. this page is from avr-libc, version 2.1.0, dated Sat Jan 29 2022, and it's the avr_stdint(3) manual. mwah 💋🦋✨