mirror of https://github.com/mkerrisk/man-pages
90 lines
2.6 KiB
Groff
90 lines
2.6 KiB
Groff
.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
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.\"
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.\" %%%LICENSE_START(VERBATIM)
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.\" Permission is granted to make and distribute verbatim copies of this
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.\" manual provided the copyright notice and this permission notice are
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.\" preserved on all copies.
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.\"
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.\" Permission is granted to copy and distribute modified versions of this
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.\" manual under the conditions for verbatim copying, provided that the
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.\" entire resulting derived work is distributed under the terms of a
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.\" permission notice identical to this one.
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.\"
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.\" Since the Linux kernel and libraries are constantly changing, this
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.\" manual page may be incorrect or out-of-date. The author(s) assume no
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.\" responsibility for errors or omissions, or for damages resulting from
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.\" the use of the information contained herein. The author(s) may not
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.\" have taken the same level of care in the production of this manual,
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.\" which is licensed free of charge, as they might when working
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.\" professionally.
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.\"
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.\" Formatted or processed versions of this manual, if unaccompanied by
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.\" the source, must acknowledge the copyright and authors of this work.
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.\" %%%LICENSE_END
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.\"
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.\" References consulted:
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.\" Linux libc source code
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.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
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.\" 386BSD man pages
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.\" Modified Sat Jul 24 19:32:25 1993 by Rik Faith (faith@cs.unc.edu)
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.TH GCVT 3 2010-09-20 "" "Linux Programmer's Manual"
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.SH NAME
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gcvt \- convert a floating-point number to a string
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.SH SYNOPSIS
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.nf
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.B #include <stdlib.h>
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.sp
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.BI "char *gcvt(double " number ", size_t " ndigit ", char *" buf );
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.fi
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.sp
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.in -4n
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Feature Test Macro Requirements for glibc (see
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.BR feature_test_macros (7)):
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.in
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.sp
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.BR gcvt ():
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.ad l
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.PD 0
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.RS 4
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.TP 4
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Since glibc 2.12:
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.nf
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_SVID_SOURCE ||
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(_XOPEN_SOURCE\ >=\ 500 ||
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_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED) &&
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!(_POSIX_C_SOURCE\ >=\ 200112L || _XOPEN_SOURCE\ >=\ 600)
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.fi
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.TP 4
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Before glibc 2.12:
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_SVID_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
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_XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
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.RE
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.PD
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.ad b
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.SH DESCRIPTION
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The
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.BR gcvt ()
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function converts \fInumber\fP to a minimal length null-terminated
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ASCII string and stores the result in \fIbuf\fP.
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It produces \fIndigit\fP significant digits in either
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.BR printf (3)
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F format or E format.
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.SH RETURN VALUE
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The
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.BR gcvt ()
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function returns the address of the string pointed to
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by \fIbuf\fP.
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.SH CONFORMING TO
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Marked as LEGACY in POSIX.1-2001.
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POSIX.1-2008 removes the specification of
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.BR gcvt (),
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recommending the use of
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.BR sprintf (3)
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instead (though
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.BR snprintf (3)
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may be preferable).
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.SH SEE ALSO
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.BR ecvt (3),
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.BR fcvt (3),
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.BR sprintf (3)
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