ECVT

Section: Linux Programmer's Manual (3)
Updated: 1999-06-25
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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);

DESCRIPTION

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.

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.

NOTES

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').

This document was created by man2html, using the manual pages.
Time: 22:15:27 GMT, February 02, 2008