mirror of https://github.com/mkerrisk/man-pages
190 lines
3.9 KiB
Groff
190 lines
3.9 KiB
Groff
.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
|
|
.\"
|
|
.\" %%%LICENSE_START(GPLv2+_DOC_ONEPARA)
|
|
.\" This is free documentation; you can redistribute it and/or
|
|
.\" modify it under the terms of the GNU General Public License as
|
|
.\" published by the Free Software Foundation; either version 2 of
|
|
.\" the License, or (at your option) any later version.
|
|
.\" %%%LICENSE_END
|
|
.\"
|
|
.\" References consulted:
|
|
.\" GNU glibc-2 source code and manual
|
|
.\" Dinkumware C library reference http://www.dinkumware.com/
|
|
.\" OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
|
|
.\"
|
|
.TH WCSNRTOMBS 3 2015-04-19 "GNU" "Linux Programmer's Manual"
|
|
.SH NAME
|
|
wcsnrtombs \- convert a wide-character string to a multibyte string
|
|
.SH SYNOPSIS
|
|
.nf
|
|
.B #include <wchar.h>
|
|
.sp
|
|
.BI "size_t wcsnrtombs(char *" dest ", const wchar_t **" src ", size_t " nwc ,
|
|
.BI " size_t " len ", mbstate_t *" ps );
|
|
.fi
|
|
.sp
|
|
.in -4n
|
|
Feature Test Macro Requirements for glibc (see
|
|
.BR feature_test_macros (7)):
|
|
.in
|
|
.sp
|
|
.BR wcsnrtombs ():
|
|
.PD 0
|
|
.ad l
|
|
.RS 4
|
|
.TP 4
|
|
Since glibc 2.10:
|
|
_XOPEN_SOURCE\ >=\ 700 || _POSIX_C_SOURCE\ >=\ 200809L
|
|
.TP
|
|
Before glibc 2.10:
|
|
_GNU_SOURCE
|
|
.RE
|
|
.ad
|
|
.PD
|
|
.SH DESCRIPTION
|
|
The
|
|
.BR wcsnrtombs ()
|
|
function is like the
|
|
.BR wcsrtombs (3)
|
|
function,
|
|
except that the number of wide characters to be converted,
|
|
starting at
|
|
.IR *src ,
|
|
is limited to
|
|
.IR nwc .
|
|
.PP
|
|
If
|
|
.I dest
|
|
is not NULL,
|
|
the
|
|
.BR wcsnrtombs ()
|
|
function converts
|
|
at most
|
|
.I nwc
|
|
wide characters from
|
|
the wide-character string
|
|
.I *src
|
|
to a multibyte string starting at
|
|
.IR dest .
|
|
At most
|
|
.I len
|
|
bytes are written to
|
|
.IR dest .
|
|
The shift state
|
|
.I *ps
|
|
is updated.
|
|
The conversion is effectively performed by repeatedly
|
|
calling
|
|
.IR "wcrtomb(dest, *src, ps)" ,
|
|
as long as this call succeeds,
|
|
and then incrementing
|
|
.I dest
|
|
by the
|
|
number of bytes written and
|
|
.I *src
|
|
by one.
|
|
The conversion can stop for three reasons:
|
|
.IP 1. 3
|
|
A wide character has been encountered that can not be represented as a
|
|
multibyte sequence (according to the current locale).
|
|
In this case,
|
|
.I *src
|
|
is left pointing to the invalid wide character,
|
|
.I (size_t)\ \-1
|
|
is returned,
|
|
and
|
|
.I errno
|
|
is set to
|
|
.BR EILSEQ .
|
|
.IP 2.
|
|
.I nwc
|
|
wide characters have been
|
|
converted without encountering a null wide character (L\(aq\\0\(aq),
|
|
or the length limit forces a stop.
|
|
In this case,
|
|
.I *src
|
|
is left pointing
|
|
to the next wide character to be converted, and the number of bytes written
|
|
to
|
|
.I dest
|
|
is returned.
|
|
.IP 3.
|
|
The wide-character string has been completely converted, including the
|
|
terminating null wide character (which has the side effect of bringing back
|
|
.I *ps
|
|
to the initial state).
|
|
In this case,
|
|
.I *src
|
|
is set to NULL, and the number
|
|
of bytes written to
|
|
.IR dest ,
|
|
excluding the terminating null byte (\(aq\\0\(aq), is
|
|
returned.
|
|
.PP
|
|
If
|
|
.IR dest
|
|
is NULL,
|
|
.I len
|
|
is ignored,
|
|
and the conversion proceeds as above,
|
|
except that the converted bytes are not written out to memory, and that
|
|
no destination length limit exists.
|
|
.PP
|
|
In both of the above cases,
|
|
if
|
|
.I ps
|
|
is NULL, a static anonymous
|
|
state known only to the
|
|
.BR wcsnrtombs ()
|
|
function is used instead.
|
|
.PP
|
|
The programmer must ensure that there is room for at least
|
|
.I len
|
|
bytes
|
|
at
|
|
.IR dest .
|
|
.SH RETURN VALUE
|
|
The
|
|
.BR wcsnrtombs ()
|
|
function returns
|
|
the number of bytes that make up the
|
|
converted part of multibyte sequence,
|
|
not including the terminating null byte.
|
|
If a wide character was encountered which
|
|
could not be converted,
|
|
.I (size_t)\ \-1
|
|
is returned, and
|
|
.I errno
|
|
set to
|
|
.BR EILSEQ .
|
|
.SH ATTRIBUTES
|
|
For an explanation of the terms used in this section, see
|
|
.BR attributes (7).
|
|
.TS
|
|
allbox;
|
|
lb lb lbw29
|
|
l l l.
|
|
Interface Attribute Value
|
|
T{
|
|
.BR wcsnrtombs ()
|
|
T} Thread safety MT-Unsafe race:wcsnrtombs/!ps
|
|
.TE
|
|
|
|
.SH CONFORMING TO
|
|
POSIX.1-2008.
|
|
.SH NOTES
|
|
The behavior of
|
|
.BR wcsnrtombs ()
|
|
depends on the
|
|
.B LC_CTYPE
|
|
category of the
|
|
current locale.
|
|
.PP
|
|
Passing NULL as
|
|
.I ps
|
|
is not multithread safe.
|
|
.SH SEE ALSO
|
|
.BR iconv (3),
|
|
.BR mbsinit (3),
|
|
.BR wcsrtombs (3)
|