Standards / Extensions | C or C++ | Dependencies |
---|---|---|
C99 |
both |
z/OS V1R8 |
#define _ISOC99_SOURCE
#include <math.h>
int isinf(real-floating x);
#define __STDC_WANT_DEC_FP__
#include <math.h>
int isinf(real-floating x); /* C only */
int isinf(decimal-floating x); /* C only */
bool isinf(real-floating x); /* C++ only */
#define _TR1_C99
#include <math.h>
bool isinf(real-floating x); /* C++ only */
The isinf() macro or function template determines if its argument is plus or minus infinity.
Function | Hex | IEEE |
---|---|---|
isinf | X | X |
The isinf() macro returns 1 if the argument is plus or minus infinity, else returns 0. The C++ function template returns true if the argument is plus or minus infinity, else returns false.
Special behavior in hex: The isinf() macro returns zero. The C++ function template returns false.