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diff --git a/man-pages-posix-2013/man3p/rint.3p b/man-pages-posix-2013/man3p/rint.3p new file mode 100644 index 0000000..4a97551 --- /dev/null +++ b/man-pages-posix-2013/man3p/rint.3p @@ -0,0 +1,130 @@ +'\" et +.TH RINT "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH 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. + +.SH NAME +rint, +rintf, +rintl +\(em round-to-nearest integral value +.SH SYNOPSIS +.LP +.nf +#include <math.h> +.P +double rint(double \fIx\fP); +float rintf(float \fIx\fP); +long double rintl(long double \fIx\fP); +.fi +.SH 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\(hy2008 defers to the ISO\ C standard. +.P +These functions shall return the integral value (represented as a +.BR double ) +nearest +.IR x +in the direction of the current rounding mode. The current rounding +mode is implementation-defined. +.P +If the current rounding mode rounds toward negative infinity, then +\fIrint\fR() +shall be equivalent to +.IR "\fIfloor\fR\^(\|)". +If the current rounding mode rounds toward positive infinity, then +\fIrint\fR() +shall be equivalent to +.IR "\fIceil\fR\^(\|)". +If the current rounding mode rounds towards zero, then +\fIrint\fR() +shall be equivalent to +.IR "\fItrunc\fR\^(\|)". +If the current rounding mode rounds towards nearest, then +\fIrint\fR() +differs from +.IR "\fIround\fR\^(\|)" +in that halfway cases are rounded to even rather than away from zero. +.P +These functions differ from the +\fInearbyint\fR(), +\fInearbyintf\fR(), +and +\fInearbyintl\fR() +functions only in that they may raise the inexact floating-point +exception if the result differs in value from the argument. +.P +An application wishing to check for error situations should set +.IR errno +to zero and call +.IR feclearexcept (FE_ALL_EXCEPT) +before calling these functions. On return, if +.IR errno +is non-zero or \fIfetestexcept\fR(FE_INVALID | FE_DIVBYZERO | +FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has occurred. +.SH "RETURN VALUE" +Upon successful completion, these functions shall return the integer +(represented as a double precision number) nearest +.IR x +in the direction of the current rounding mode. +The result shall have the same sign as +.IR x . +.P +If +.IR x +is NaN, a NaN shall be returned. +.P +If +.IR x +is \(+-0 or \(+-Inf, +.IR x +shall be returned. +.SH ERRORS +No errors are defined. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +The integral value returned by these functions need not be expressible +as an +.BR intmax_t . +The return value should be tested before assigning it to an integer type +to avoid the undefined results of an integer overflow. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIabs\fR\^(\|)", +.IR "\fIceil\fR\^(\|)", +.IR "\fIfeclearexcept\fR\^(\|)", +.IR "\fIfetestexcept\fR\^(\|)", +.IR "\fIfloor\fR\^(\|)", +.IR "\fIisnan\fR\^(\|)", +.IR "\fInearbyint\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "Section 4.19" ", " "Treatment of Error Conditions for Mathematical Functions", +.IR "\fB<math.h>\fP" +.SH 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 . |