gcvt(3) - BetterMan

gcvt(3)

convert a floating-point number to a string

distropkg manpages-dev@6.9.1-1dataset 2026-04-01T06:19:02Z+debian+ec4110e+mandoc:1.14.6-4

Synopsis

#include <stdlib.h>
char *gcvt(double 
number
, int 
ndigit
, char *
buf
);
gcvt
():
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

—

NAME

gcvt - convert a floating-point number to a string

SYNOPSIS

bash

#include <stdlib.h>

bash

char *gcvt(double \nnumber\n, int \nndigit\n, char *\nbuf\n);

gcvt():

bash


\n
    Since glibc 2.17
\n
        (_XOPEN_SOURCE >= 500 && ! (_POSIX_C_SOURCE >= 200809L))
\n
            || /* glibc >= 2.20 */ _DEFAULT_SOURCE
\n
            || /* glibc <= 2.19 */ _SVID_SOURCE
\n
    glibc 2.12 to glibc 2.16:
\n
        (_XOPEN_SOURCE >= 500 && ! (_POSIX_C_SOURCE >= 200112L))
\n
            || _SVID_SOURCE
\n
    Before glibc 2.12:
\n
        _SVID_SOURCE || _XOPEN_SOURCE >= 500

The gcvt() function converts number to a minimal length null-terminated ASCII string and stores the result in buf. It produces ndigit significant digits in either printf(3) F format or E format.