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+'\" t
+.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
+.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
+.\" <mtk.manpages@gmail.com>
+.\"
+.\" SPDX-License-Identifier: Linux-man-pages-copyleft
+.\"
+.\" References consulted:
+.\" Linux libc source code
+.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
+.\" 386BSD man pages
+.\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu)
+.\" Modified 2004-10-31 by aeb
+.\"
+.TH ldexp 3 2024-05-02 "Linux man-pages (unreleased)"
+.SH NAME
+ldexp, ldexpf, ldexpl \- multiply floating-point number by integral power of 2
+.SH LIBRARY
+Math library
+.RI ( libm ", " \-lm )
+.SH SYNOPSIS
+.nf
+.B #include <math.h>
+.P
+.BI "double ldexp(double " x ", int " exp );
+.BI "float ldexpf(float " x ", int " exp );
+.BI "long double ldexpl(long double " x ", int " exp );
+.fi
+.P
+.RS -4
+Feature Test Macro Requirements for glibc (see
+.BR feature_test_macros (7)):
+.RE
+.P
+.BR ldexpf (),
+.BR ldexpl ():
+.nf
+ _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
+ || /* Since glibc 2.19: */ _DEFAULT_SOURCE
+ || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
+.fi
+.SH DESCRIPTION
+These functions return the result of multiplying the floating-point number
+.I x
+by 2 raised to the power
+.IR exp .
+.SH RETURN VALUE
+On success, these functions return
+.IR "x * (2\[ha]exp)" .
+.P
+If
+.I exp
+is zero, then
+.I x
+is returned.
+.P
+If
+.I x
+is a NaN,
+a NaN is returned.
+.P
+If
+.I x
+is positive infinity (negative infinity),
+positive infinity (negative infinity) is returned.
+.P
+If the result underflows,
+a range error occurs,
+and zero is returned.
+.P
+If the result overflows,
+a range error occurs,
+and the functions return
+.BR HUGE_VAL ,
+.BR HUGE_VALF ,
+or
+.BR HUGE_VALL ,
+respectively, with a sign the same as
+.IR x .
+.SH ERRORS
+See
+.BR math_error (7)
+for information on how to determine whether an error has occurred
+when calling these functions.
+.P
+The following errors can occur:
+.TP
+Range error, overflow
+.I errno
+is set to
+.BR ERANGE .
+An overflow floating-point exception
+.RB ( FE_OVERFLOW )
+is raised.
+.TP
+Range error, underflow
+.I errno
+is set to
+.BR ERANGE .
+An underflow floating-point exception
+.RB ( FE_UNDERFLOW )
+is raised.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lbx lb lb
+l l l.
+Interface Attribute Value
+T{
+.na
+.nh
+.BR ldexp (),
+.BR ldexpf (),
+.BR ldexpl ()
+T} Thread safety MT-Safe
+.TE
+.SH STANDARDS
+C11, POSIX.1-2008.
+.SH HISTORY
+C99, POSIX.1-2001.
+.P
+The variant returning
+.I double
+also conforms to
+SVr4, 4.3BSD, C89.
+.SH SEE ALSO
+.BR frexp (3),
+.BR modf (3),
+.BR scalbln (3)