5.80 Boolean type and <stdbool.h> in C99

C99 introduces the native type _Bool.

The associated standard header <stdbool.h> introduces the macros bool, true and false for Boolean tests. For example:

#include <stdbool.h>
bool foo(FILE *str)
    bool err = false;
    if (!fflush(str))
        err = true;
    return err;


The C99 semantics for bool are intended to match those of C++.

Related concepts
5.64 New library features of C99
5.78 Additional <math.h> library functions in C99
5.79 Complex numbers in C99
5.81 Extended integer types and functions in <inttypes.h> and <stdint.h> in C99
5.82 <fenv.h> floating-point environment access in C99
5.83 <stdio.h> snprintf family of functions in C99
5.84 <tgmath.h> type-generic math macros in C99
5.85 <wchar.h> wide character I/O functions in C99
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