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diff --git a/man3p/rint.3p b/man3p/rint.3p new file mode 100644 index 000000000..3c6da95da --- /dev/null +++ b/man3p/rint.3p @@ -0,0 +1,100 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "RINT" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" rint +.SH NAME +rint, rintf, rintl \- round-to-nearest integral value +.SH SYNOPSIS +.LP +\fB#include <math.h> +.br +.sp +double rint(double\fP \fIx\fP\fB); +.br +float rintf(float\fP \fIx\fP\fB); +.br +long double rintl(long double\fP \fIx\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +These functions shall return the integral value (represented as a +\fBdouble\fP) nearest \fIx\fP in the direction of the +current rounding mode. The current rounding mode is implementation-defined. +.LP +If the current rounding mode rounds toward negative infinity, then +\fIrint\fP() shall be equivalent to \fIfloor\fP() . If the current +rounding mode rounds toward positive infinity, then \fIrint\fP() shall +be +equivalent to \fIceil\fP() . +.LP +These functions differ from the \fInearbyint\fP(), \fInearbyintf\fP(), +and \fInearbyintl\fP() +functions only in that they may raise the inexact floating-point exception +if the result differs in value from the argument. +.LP +An application wishing to check for error situations should set \fIerrno\fP +to zero and call +\fIfeclearexcept\fP(FE_ALL_EXCEPT) before calling these functions. +On return, if \fIerrno\fP is non-zero or +\fIfetestexcept\fP(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) +is non-zero, an error has occurred. +.SH RETURN VALUE +.LP +Upon successful completion, these functions shall return the integer +(represented as a double precision number) nearest \fIx\fP +in the direction of the current rounding mode. +.LP +If +\fIx\fP is NaN, a NaN shall be returned. +.LP +If \fIx\fP is \(+-0 or \(+-Inf, \fIx\fP shall be returned. +.LP +If the correct value would cause overflow, a range error shall occur +and \fIrint\fP(), \fIrintf\fP(), and \fIrintl\fP() shall +return the value of the macro \(+-HUGE_VAL, \(+-HUGE_VALF, and \(+-HUGE_VALL +(with the same sign as \fIx\fP), +respectively. +.SH ERRORS +.LP +These functions shall fail if: +.TP 7 +Range\ Error +The result would cause an overflow. +.LP +If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, +then \fIerrno\fP shall be set to [ERANGE]. If the +integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, +then the overflow floating-point exception shall be raised. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +On error, the expressions (math_errhandling & MATH_ERRNO) and (math_errhandling +& MATH_ERREXCEPT) are independent of +each other, but at least one of them must be non-zero. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIabs\fP() , \fIceil\fP() , \fIfeclearexcept\fP() , \fIfetestexcept\fP() +, \fIfloor\fP() , \fIisnan\fP() , \fInearbyint\fP() , the +Base Definitions volume of IEEE\ Std\ 1003.1-2001, Section 4.18, Treatment +of Error Conditions for Mathematical Functions, \fI<math.h>\fP +.SH 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 . |