.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
.\"
.\" %%%LICENSE_START(VERBATIM)
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.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
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.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
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.\" 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.\" manual page may be incorrect or out-of-date.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
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.\" References consulted:
.\"     Linux libc source code
.\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
.\"     386BSD man pages
.\" Modified Sat Jul 24 19:32:25 1993 by Rik Faith (faith@cs.unc.edu)
.TH GCVT 3 2016-03-15 "" "Linux Programmer's Manual"
.SH NAME
gcvt \- convert a floating-point number to a string
.SH SYNOPSIS
.nf
.B #include <stdlib.h>
.sp
.BI "char *gcvt(double " number ", int " ndigit ", char *" buf );
.fi
.sp
.in -4n
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.in
.sp
.BR gcvt ():
.ad l
.PD 0
.RS 4
.TP 4
Since glibc 2.12:
.nf
(_XOPEN_SOURCE\ >=\ 500) ! (_POSIX_C_SOURCE\ >=\ 200112L)
    || /* Glibc since 2.19: */ _DEFAULT_SOURCE
    || /* Glibc versions <= 2.19: */ _SVID_SOURCE
.fi
.TP 4
Before glibc 2.12:
_SVID_SOURCE || _XOPEN_SOURCE\ >=\ 500
.\"    || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
.RE
.PD
.ad b
.SH DESCRIPTION
The
.BR gcvt ()
function converts \fInumber\fP to a minimal length null-terminated
ASCII string and stores the result in \fIbuf\fP.
It produces \fIndigit\fP significant digits in either
.BR printf (3)
F format or E format.
.SH RETURN VALUE
The
.BR gcvt ()
function returns the address of the string pointed to
by \fIbuf\fP.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lb lb lb
l l l.
Interface	Attribute	Value
T{
.BR gcvt ()
T}	Thread safety	MT-Safe
.TE

.SH CONFORMING TO
Marked as LEGACY in POSIX.1-2001.
POSIX.1-2008 removes the specification of
.BR gcvt (),
recommending the use of
.BR sprintf (3)
instead (though
.BR snprintf (3)
may be preferable).
.SH SEE ALSO
.BR ecvt (3),
.BR fcvt (3),
.BR sprintf (3)
.SH COLOPHON
This page is part of release 4.10 of the Linux
.I man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
\%https://www.kernel.org/doc/man\-pages/.