'\" 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 .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)