ISLESSEQUAL(3P) POSIX Programmer's Manual ISLESSEQUAL(3P)
PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond-
ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
NAME
islessequal - test if x is less than or equal to y
SYNOPSIS
#include <math.h>
int islessequal(real-floating x, real-floating y);
DESCRIPTION
The islessequal() macro shall determine whether its first argument is less than or equal to its second argument. The value of islessequal(
x, y) shall be equal to (x) <= (y); however, unlike (x) <= (y), islessequal( x, y) shall not raise the invalid floating-point exception
when x and y are unordered.
RETURN VALUE
Upon successful completion, the islessequal() 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 argu-
ment shall be an expression of real-floating type.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
isgreater(), isgreaterequal(), isless(), 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 Technol-
ogy -- 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 ISLESSEQUAL(3P)