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diff --git a/man-pages-posix-2017/man3p/llround.3p b/man-pages-posix-2017/man3p/llround.3p new file mode 100644 index 0000000..b7c93aa --- /dev/null +++ b/man-pages-posix-2017/man3p/llround.3p @@ -0,0 +1,151 @@ +'\" et +.TH LLROUND "3P" 2017 "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 +llround, +llroundf, +llroundl +\(em round to nearest integer value +.SH SYNOPSIS +.LP +.nf +#include <math.h> +.P +long long llround(double \fIx\fP); +long long llroundf(float \fIx\fP); +long long llroundl(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\(hy2017 defers to the ISO\ C standard. +.P +These functions shall round their argument to the nearest integer +value, rounding halfway cases away from zero, regardless of the current +rounding direction. +.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 rounded +integer value. +.P +If +.IR x +is NaN, a domain error shall occur, and an unspecified value is +returned. +.P +If +.IR x +is +Inf, a domain error shall occur and an unspecified value is +returned. +.P +If +.IR x +is \-Inf, a domain error shall occur and an unspecified value is +returned. +.P +If the correct value is positive and too large to represent as a +.BR "long long" , +an unspecified value shall be returned. +On systems that support the IEC 60559 Floating-Point option, a domain +error shall occur; +otherwise, a +domain +error may occur. +.P +If the correct value is negative and too large to represent as a +.BR "long long" , +an unspecified value shall be returned. +On systems that support the IEC 60559 Floating-Point option, a domain +error shall occur; +otherwise, a +domain +error may occur. +.SH ERRORS +These functions shall fail if: +.IP "Domain\ Error" 12 +The +.IR x +argument is NaN or \(+-Inf, or the correct value is not representable +as an integer. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [EDOM] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the invalid floating-point exception shall be raised. +.RE +.P +These functions may fail if: +.IP "Domain\ Error" 12 +The correct value is not representable as an integer. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [EDOM] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the invalid floating-point exception shall be raised. +.RE +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +On error, the expressions (\fImath_errhandling\fR & MATH_ERRNO) and +(\fImath_errhandling\fR & MATH_ERREXCEPT) are independent of each +other, but at least one of them must be non-zero. +.SH RATIONALE +These functions differ from the +\fIllrint\fR() +functions in that the default rounding direction for the +\fIllround\fR() +functions round halfway cases away from zero and need not raise the +inexact floating-point exception for non-integer arguments that round +to within the range of the return type. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIfeclearexcept\fR\^(\|)", +.IR "\fIfetestexcept\fR\^(\|)", +.IR "\fIlround\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 4.20" ", " "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 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 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 . +.PP +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 . |