xref: /illumos-gate/usr/src/man/man3c/mbrlen.3c (revision e86372a01d2d16a5dd4a64e144ed978ba17fe7dd)

Sun Microsystems, Inc. gratefully acknowledges The Open Group for
permission to reproduce portions of its copyrighted documentation.
Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.

The Institute of Electrical and Electronics Engineers and The Open
Group, have given us permission to reprint portions of their
documentation.

In the following statement, the phrase ``this text'' refers to portions
of the system documentation.

Portions of this text are reprinted and reproduced in electronic form
in the SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition,
Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6,
Copyright (C) 2001-2004 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy
between these versions and the original IEEE and The Open Group
Standard, the original IEEE and The Open Group Standard is the referee
document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html.

This notice shall appear on any product containing this material.

The contents of this file are subject to the terms of the
Common Development and Distribution License (the "License").
You may not use this file except in compliance with the License.

You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
or http://www.opensolaris.org/os/licensing.
See the License for the specific language governing permissions
and limitations under the License.

When distributing Covered Code, include this CDDL HEADER in each
file and include the License file at usr/src/OPENSOLARIS.LICENSE.
If applicable, add the following below this CDDL HEADER, with the
fields enclosed by brackets "[]" replaced with your own identifying
information: Portions Copyright [yyyy] [name of copyright owner]


Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
Portions Copyright (c) 2003, Sun Microsystems, Inc. All Rights Reserved.
Copyright 2014 Garrett D'Amore <garrett@damore.org>

MBRLEN 3C "Jun 21, 2014"
NAME
mbrlen, mbrlen_l - get number of bytes in a character (restartable)
SYNOPSIS

#include <wchar.h>

size_t mbrlen(const char *restrict s, size_t n, mbstate_t *restrict ps);

#include <wchar.h>
#include <xlocale.h>

size_t mbrlen_l(const char *restrict s, size_t n, mbstate_t *restrict ps,
 locale_t loc);
DESCRIPTION

If s is not a null pointer, mbrlen() and mbrlen_l() determine the number of bytes constituting the character pointed to by s. The call

mbrlen(s, n, ps);

is equivalent to:

mbstate_t internal; mbrtowc(NULL, s, n, ps != NULL ? ps : &internal);

If ps is a null pointer, the mbrlen() and mbrlen_l() functions use their own internal mbstate_t object, which is initialized at program startup to the initial conversion state. Otherwise, the mbstate_t object pointed to by ps is used to completely describe the current conversion state of the associated character sequence. The implemenation will behave as if no function defined in the Reference Manual calls mbrlen().

The behavior of mbrlen() is affected by the LC_CTYPE category of the current locale. See environ(5). The behavior of mbrlen_l() does not use the current enivronment and instead uses the locale specified by loc.

RETURN VALUES

The mbrlen() and mbrlen_l() functions return the first of the following that applies: 0

If the next n or fewer bytes complete the character that corresponds to the null wide-character.

positive

If the next n or fewer bytes complete a valid character; the value returned is the number of bytes that complete the character.

(size_t)-2

If the next n bytes contribute to an incomplete but potentially valid character, and all n bytes have been processed. When n has at least the value of the MB_CUR_MAX macro, this case can only occur if s points at a sequence of redundant shift sequences (for implementations with state-dependent encodings).

(size_t)-1

If an encoding error occurs, in which case the next n or fewer bytes do not contribute to a complete and valid character. In this case, EILSEQ is stored in errno and the conversion state is undefined.

ERRORS

The mbrlen() and mbrlen_l() functions may fail if: EINVAL

The ps argument points to an object that contains an invalid conversion state.

EILSEQ

Invalid character sequence is detected.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability See below.
MT-Level MT-Safe

The mbrlen() function is Standard. The mbrlen_l() function is Uncommitted.

SEE ALSO

mbrtowc(3C), mbsinit(3C), newlocale(3C), setlocale(3C), attributes(5), environ(5), standards(5)

NOTES

If ps is not a null pointer, mbrlen() uses the mbstate_t object pointed to by ps and the function can be used safely in multithreaded applications, as long as setlocale(3C) is not being called to change the locale or a per-thread locale has been installed on the calling thread with uselocale(3C). If ps is a null pointer, mbrlen() uses its internal mbstate_t object and the function is Unsafe in multithreaded applications.