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NAME
float_t, double_t - most efficient floating types
LIBRARY
Math library (libm)
SYNOPSIS
#include <math.h>
typedef /* ... */ float_t;
typedef /* ... */ double_t;
DESCRIPTION
The implementation's most efficient floating types at least as wide as float and double respectively.
Their type depends on the value of the macro FLT_EVAL_METHOD (defined in <float.h>):
FLT_EVAL_METHOD float_t double_t
────────────────────────────────────────────
0 float double
1 double double
2 long double long double
For other values of FLT_EVAL_METHOD, the types of float_t and double_t are implementation-defined.
STANDARDS
C11, POSIX.1-2008.
HISTORY
C99, POSIX.1-2001.
SEE ALSO
float.h(0p), math.h(0p)
Linux man-pages 6.7 2023-10-31 double_t(3type)