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diff --git a/man-pages-posix-2013/man3p/scalbln.3p b/man-pages-posix-2013/man3p/scalbln.3p new file mode 100644 index 0000000..bb6684c --- /dev/null +++ b/man-pages-posix-2013/man3p/scalbln.3p @@ -0,0 +1,172 @@ +'\" et +.TH SCALBLN "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 +scalbln, +scalblnf, +scalblnl, +scalbn, +scalbnf, +scalbnl +\(em compute exponent using FLT_RADIX +.SH SYNOPSIS +.LP +.nf +#include <math.h> +.P +double scalbln(double \fIx\fP, long \fIn\fP); +float scalblnf(float \fIx\fP, long \fIn\fP); +long double scalblnl(long double \fIx\fP, long \fIn\fP); +double scalbn(double \fIx\fP, int \fIn\fP); +float scalbnf(float \fIx\fP, int \fIn\fP); +long double scalbnl(long double \fIx\fP, int \fIn\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 compute \fIx\fR\ *\ FLT_RADIX\fI\s-3\un\d\s+3\fR +efficiently, not normally by computing FLT_RADIX\fI\s-3\un\d\s+3\fR +explicitly. +.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 +\fIx\fR\ *\ FLT_RADIX\fI\s-3\un\d\s+3\fR. +.P +If the result would cause overflow, a range error shall occur and these +functions shall return \(+-HUGE_VAL, \(+-HUGE_VALF, and \(+-HUGE_VALL +(according to the sign of +.IR x ) +as appropriate for the return type of the function. +.P +If the correct value would cause underflow, +and is not representable, +a range error may occur, and +\fIscalbln\fR(), +\fIscalblnf\fR(), +\fIscalblnl\fR(), +\fIscalbn\fR(), +\fIscalbnf\fR(), +and +\fIscalbnl\fR() +shall return +0.0, or +(if IEC 60559 Floating-Point is not supported) an implementation-defined +value no greater in magnitude than DBL_MIN, FLT_MIN, LDBL_MIN, DBL_MIN, +FLT_MIN, and LDBL_MIN, respectively. +.P +If +.IR x +is NaN, a NaN shall be returned. +.P +If +.IR x +is \(+-0 or \(+-Inf, +.IR x +shall be returned. +.P +If +.IR n +is 0, +.IR x +shall be returned. +.P +If the correct value would cause underflow, and is representable, a +range error may occur and the correct value shall be returned. +.SH ERRORS +These functions shall fail if: +.IP "Range\ Error" 12 +The result overflows. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [ERANGE] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the overflow floating-point exception shall be raised. +.RE +.br +.P +These functions may fail if: +.IP "Range\ Error" 12 +The result underflows. +.RS 12 +.P +If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is +non-zero, then +.IR errno +shall be set to +.BR [ERANGE] . +If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is +non-zero, then the underflow 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 are named so as to avoid conflicting with the +historical definition of the +.IR scalb (\|) +function from the Single UNIX Specification. The difference is that the +.IR scalb (\|) +function has a second argument of +.BR double +instead of +.BR int . +The +.IR scalb (\|) +function is not part of the ISO\ C standard. The three functions whose second +type is +.BR long +are provided because the factor required to scale from the smallest +positive floating-point value to the largest finite one, on many +implementations, is too large to represent in the minimum-width +.BR int +format. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIfeclearexcept\fR\^(\|)", +.IR "\fIfetestexcept\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 . |