NAME
ecvt, fcvt - convert a floating-point number to a string
SYNOPSIS
#include <stdlib.h>
char *ecvt(double number, int ndigits, int *decpt, int *sign);
char *fcvt(double number, int ndigits, int *decpt, int *sign);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
ecvt(), fcvt(): _SVID_SOURCE || _XOPEN_SOURCE >= 500
DESCRIPTION
The ecvt() function converts number to a null-terminated string of
ndigits digits (where ndigits is reduced to a system-specific limit
determined by the precision of a double), and returns a pointer to the
string. The high-order digit is nonzero, 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 nonzero
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.
RETURN VALUE
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().
CONFORMING TO
SVr2; marked as LEGACY in POSIX.1-2001. POSIX.1-2008 removes the
specifications of ecvt() and fcvt(), recommending the use of sprintf(3)
instead (though snprintf(3) may be preferable).
NOTES
Linux libc4 and libc5 specified the type of ndigits as size_t. Not all
locales use a point as the radix character ("decimal point").
SEE ALSO
ecvt_r(3), gcvt(3), qecvt(3), setlocale(3), sprintf(3)
COLOPHON
This page is part of release 3.24 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2009-03-15 ECVT(3)