PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       islessgreater — test if x is less than or greater than y

SYNOPSIS

       #include <math.h>

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

DESCRIPTION

       The  functionality  described  on  this  reference  page is aligned with the ISO C standard. Any conflict
       between the requirements described  here  and  the  ISO C  standard  is  unintentional.  This  volume  of
       POSIX.1‐2008 defers to the ISO C standard.

       The  islessgreater()  macro  shall  determine whether its first argument is less than or greater than its
       second  argument.  The  islessgreater(x,  y)  macro  is  similar  to   (x) < (y) || (x) > (y);   however,
       islessgreater(x,  y) shall not raise the invalid floating-point exception when x and y are unordered (nor
       shall it evaluate x and y twice).

RETURN VALUE

       Upon successful completion, the islessgreater() macro shall return the value of (x) < (y) || (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(), isless(), islessequal(), isunordered()

       The Base Definitions volume of POSIX.1‐2008, <math.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers,  Inc
       and  The  Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2013                                 ISLESSGREATER(3POSIX)