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diff --git a/man-pages-posix-2003/man3p/ldexp.3p b/man-pages-posix-2003/man3p/ldexp.3p new file mode 100644 index 0000000..dc5f780 --- /dev/null +++ b/man-pages-posix-2003/man3p/ldexp.3p @@ -0,0 +1,115 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "LDEXP" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" ldexp +.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 +ldexp, ldexpf, ldexpl \- load exponent of a floating-point number +.SH SYNOPSIS +.LP +\fB#include <math.h> +.br +.sp +double ldexp(double\fP \fIx\fP\fB, int\fP \fIexp\fP\fB); +.br +float ldexpf(float\fP \fIx\fP\fB, int\fP \fIexp\fP\fB); +.br +long double ldexpl(long double\fP \fIx\fP\fB, int\fP \fIexp\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +These functions shall compute the quantity \fIx\fP\ *\ 2**\fIexp\fP. +.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 \fIx\fP multiplied +by 2, raised to the power \fIexp\fP. +.LP +If these functions would cause overflow, a range error shall occur +and \fIldexp\fP(), \fIldexpf\fP(), and \fIldexpl\fP() +shall return \(+-HUGE_VAL, \(+-HUGE_VALF, and \(+-HUGE_VALL (according +to the sign of \fIx\fP), respectively. +.LP +If the correct value would cause underflow, and is not representable, +a range error may occur, and either 0.0 (if +supported), or an implementation-defined value shall be +returned. +.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 \fIexp\fP is 0, \fIx\fP shall be returned. +.LP +If the correct value would cause underflow, and is representable, +a range error may occur and the correct value shall be +returned. +.SH ERRORS +.LP +These functions shall fail if: +.TP 7 +Range\ Error +The result overflows. +.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 +These functions may fail if: +.TP 7 +Range\ Error +The result underflows. +.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 underflow 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 +\fIfeclearexcept\fP(), \fIfetestexcept\fP(), \fIfrexp\fP(), \fIisnan\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 . |