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'\" t
.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.\" 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 2023-02-05 "Linux man-pages 6.03"
.SH NAME
gcvt \- convert a floating-point number to a string
.SH LIBRARY
Standard C library
.RI ( libc ", " \-lc )
.SH SYNOPSIS
.nf
.B #include <stdlib.h>
.PP
.BI "char *gcvt(double " number ", int " ndigit ", char *" buf );
.fi
.PP
.RS -4
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.RE
.PP
.BR gcvt ():
.nf
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
.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
.fi
.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
\fIbuf\fP.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.ad l
.nh
.TS
allbox;
lbx lb lb
l l l.
Interface Attribute Value
T{
.BR gcvt ()
T} Thread safety MT-Safe
.TE
.hy
.ad
.sp 1
.SH STANDARDS
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)
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