Predefined Boolean constants (since 哋它亢23)

 

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Syntax

true	(1)	(since 哋它亢23)
false	(2)	(since 哋它亢23)

Explanation

Keywords true and false represent predefined constants. They are non-lvalues of type bool.

Notes

See integral conversions for implicit conversions from bool to other types and boolean conversions for the implicit conversions from other types to bool.

Until 哋它亢23, true and false were implemented as macros provided in <stdbool.h>. An implementation may also define bool, true, and false as predefined macros in 哋它亢23 for compatibility.

Example

Run this code

#include <stdio.h>
 
int main(void)
{
    printf("%d\n%d\n", true, false);
}

Output:

1
0