__isnan

Name

__isnan -- test for infinity

Synopsis

int __isnan(double arg);

Description

__isnan() has the same specification as isnan() in POSIX 1003.1-2008 (ISO/IEC 9945-2009), except that the argument type for __isnan() is known to be double.

__isnan() is not in the source standard; it is only in the binary standard.