ecvt, fcvt — convert a floating-point number to a string
#include <stdlib.h>
char
*ecvt( |
double | number, |
int | ndigits, | |
int * | decpt, | |
int * | sign) ; |
char
*fcvt( |
double | number, |
int | ndigits, | |
int * | decpt, | |
int * | sign) ; |
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Note | ||
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The ecvt
() function converts
number
to a
null-terminated string of ndigits
digits (where
ndigits
is reduced to
an system-specific limit determined by the precision of a
double), and returns a pointer to the string. The high-order
digit is non-zero, unless number
is zero. The low order
digit is rounded. The string itself does not contain a
decimal point; however, the position of the decimal point
relative to the start of the string is stored in *decpt
. A negative value for
*decpt
means that the
decimal point is to the left of the start of the string. If
the sign of number
is
negative, *sign
is
set to a non-zero value, otherwise it is set to 0. If
number
is zero, it is
unspecified whether *decpt
is 0 or 1.
The fcvt
() function is
identical to ecvt
(), except
that ndigits
specifies the number of digits after the decimal point.
Both the ecvt
() and
fcvt
() functions return a
pointer to a static string containing the ASCII
representation of number
. The static string is
overwritten by each call to ecvt
() or fcvt
().
These functions are obsolete. Instead, sprintf(3) is recommended.
Linux libc4 and libc5 specified the type of ndigits
as size_t
. Not all locales use a
point as the radix character (`decimal point').
ecvt_r(3), gcvt(3), qecvt(3), setlocale(3), sprintf(3)
Copyright 1993 David Metcalfe (david@prism.demon.co.uk) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. References consulted: Linux libc source code Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) 386BSD man pages Modified Sat Jul 24 19:40:39 1993 by Rik Faith (faith@cs.unc.edu) Modified Fri Jun 25 12:10:47 1999 by Andries Brouwer (aeb@cwi.nl) |