double_t(3type)

💖 double_t(3type) 💖

okay bestie, welcome to the manual page for double_t — and its ride-or-die float_t — from section 3type. yes we're doing types today, and honestly? it's giving "tiny page, huge personality" ✨

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🌸 NAME 🌸

float_t, double_t — the most efficient floating types, periodt 💅

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📚 LIBRARY 📚

Math library (libm) 🧮

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✨ SYNOPSIS ✨

#include <math.h>

typedef /* ... */ float_t;
typedef /* ... */ double_t;

the /* ... */ is not me being lazy, that's literally what the page says, because the actual type is a mystery the implementation decides 🫶

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🦋 DESCRIPTION 🦋

so these are the implementation's most efficient floating types, and they're at least as wide as float and double respectively. key word at least, bestie, they can go bigger 👑

and what they actually are? depends on the value of the macro FLT_EVAL_METHOD, which lives in <float.h>:

FLT_EVAL_METHOD       float_t      double_t
────────────────────────────────────────────
       0                float        double
       1               double        double
       2          long double   long double

so like, method 0? you get plain float and double, cute and chill 🌈. method 1? both of them are double — float_t leveled up 📈. method 2? EVERYBODY is long double, main character energy only 💀✨

⚠️ and for any other values of FLT_EVAL_METHOD, the types of float_t and double_t are implementation-defined. so no guessing games, bestie — it's whatever your implementation says it is, no cap 🙈

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⭐ STANDARDS ⭐

C11, POSIX.1-2024. certified iconic 📜

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🎀 HISTORY 🎀

C99, POSIX.1-2001. so they've been around since the olden days, lowkey a legacy queen 💜

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👀 SEE ALSO 👀

• float.h(0p)
• math.h(0p)

go read those next, iykyk 🧚

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and that's the whole page!! 💖✨ this delightful little number came to you courtesy of Linux man-pages 6.20, dated 2026-02-08 — slay, ate, no crumbs 🎀💅🦋