ecvt(3) Library Functions Manual ecvt(3)

# NOME¶

ecvt, fcvt - converte um número ponto-flutuante para uma seqüencia

# BIBLIOTECA¶

Biblioteca C Padrão (libc, -lc)

# SINOPSE¶

`#include <stdlib.h>`
```[[deprecated]] char *ecvt(double number, int ndigits,
int *restrict decpt, int *restrict sign);
[[deprecated]] char *fcvt(double number, int ndigits,
int *restrict decpt, int *restrict sign);```

Requisitos de macro de teste de recursos para o glibc (consulte feature_test_macros(7)):

ecvt(), fcvt():

```
Since glibc 2.17

(_XOPEN_SOURCE >= 500 && ! (_POSIX_C_SOURCE >= 200809L))

|| /* glibc >= 2.20 */ _DEFAULT_SOURCE

|| /* glibc <= 2.19 */ _SVID_SOURCE

glibc 2.12 to glibc 2.16:

(_XOPEN_SOURCE >= 500 && ! (_POSIX_C_SOURCE >= 200112L))

|| _SVID_SOURCE

Before glibc 2.12:

_SVID_SOURCE || _XOPEN_SOURCE >= 500```

# DESCRIÇÃO¶

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.

A função fcvt() é identica a ecvt(), exceto que ndigits especifica o número de digitos após o ponto decimal.

# VALOR DE RETORNO¶

Ambas as funções ecvt() e fcvt() retornam um ponteiro para uma seqüencia estática contendo a representação ASCII de number. A seqüencia estática é sobrescrita a cada chamada a ecvt() ou fcvt().

# ATRIBUTOS¶

Para uma explicação dos termos usados nesta seção, consulte attributes(7).

 Interface Atributo Valor ecvt() Thread safety MT-Unsafe race:ecvt fcvt() Thread safety MT-Unsafe race:fcvt

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).

# NOTAS¶

Not all locales use a point as the radix character ("decimal point").