ISLESSEQUAL(P) POSIX Programmer's Manual ISLESSEQUAL(P)
islessequal - test if x is less than or equal to y
int islessequal(real-floating x, real-floating y);
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); how-
ever, unlike (x) <= (y), islessequal( x, y) shall not raise the invalid floating-point
exception when x and y are unordered.
Upon successful completion, the islessequal() macro shall return the value of (x) <= (y).
If x or y is NaN, 0 shall be returned.
No errors are defined.
The following sections are informative.
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 SYN-
OPSIS section, real-floating indicates that the argument shall be an expression of real-
isgreater() , isgreaterequal() , isless() , islessgreater() , isunordered() , the Base
Definitions volume of IEEE Std 1003.1-2001 <math.h>
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 orig-
inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 ISLESSEQUAL(P)