NAME

       isless - test if x is less than y

SYNOPSIS

       #include <math.h>

       int isless(real-floating x, real-floating y);

DESCRIPTION

       The isless() macro shall determine whether its first argument is less than its second argument. The value
       of  isless(  x,  y) shall be equal to (x) < (y); however, unlike (x) < (y), isless( x, y) shall not raise
       the invalid floating-point exception when x and y are unordered.

RETURN VALUE

       Upon successful completion, the isless() macro shall return the value of (x) < (y).

       If x or y is NaN, 0 shall be returned.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       The relational and equality operators  support  the  usual  mathematical  relationships  between  numeric
       values.  For  any  ordered  pair  of numeric values, exactly one of the relationships (less, greater, and
       equal) is true. Relational operators may raise the invalid floating-point exception when argument  values
       are  NaNs.  For a NaN and a numeric value, or for two NaNs, just the unordered relationship is true. This
       macro is a quiet (non-floating-point exception raising) version of a relational operator. It  facilitates
       writing  efficient code that accounts for NaNs without suffering the invalid floating-point exception. In
       the SYNOPSIS section, real-floating indicates that the argument shall be an expression  of  real-floating
       type.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       isgreater()  ,  isgreaterequal() , islessequal() , islessgreater() , isunordered() , the Base Definitions
       volume of IEEE Std 1003.1-2001, <math.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition,
       Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open  Group  Base
       Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers,
       Inc  and  The  Open Group. In the event of any discrepancy between this version and the original IEEE and
       The Open Group Standard, the original IEEE and The Open Group  Standard  is  the  referee  document.  The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                                   2003                                             ISLESS(P)