PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

ISLESS(3P)                POSIX Programmer's Manual               ISLESS(3P)

PROLOG         top

       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         top

       isless — test if x is less than y

SYNOPSIS         top

       #include <math.h>
       int isless(real-floating x, real-floating y);

DESCRIPTION         top

       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 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         top

       Upon successful completion, the isless() macro shall return the value
       of (x) < (y).
       If x or y is NaN, 0 shall be returned.

ERRORS         top

       No errors are defined.
       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       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         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       isgreater(3p), isgreaterequal(3p), islessequal(3p),
       islessgreater(3p), isunordered(3p)
       The Base Definitions volume of POSIX.1‐2008, math.h(0p)

COPYRIGHT         top

       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                          ISLESS(3P)

Pages that refer to this page: math.h(0p)isgreater(3p)isgreaterequal(3p)islessequal(3p)islessgreater(3p)isunordered(3p)