WCSRTOMBS(3C) Standard C Library Functions WCSRTOMBS(3C)


NAME


wcsnrtombs, wcsnrtombs_l, wcsrtombs, wcsrtombs_l - convert a wide-
character string to a character string (restartable)

SYNOPSIS


#include <wchar.h>

size_t wcsrtombs(char *restrict dst, const wchar_t **restrict src,
size_t len, mbstate_t *restrict ps);

size_t wcsnrtombs(char *restrict dst, const wchar_t **restrict src,
size_t nwc, size_t len, mbstate_t *restrict ps);

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

size_t wcsrtombs_l(char *restrict dst, const wchar_t **restrict src,
size_t len, mbstate_t *restrict ps, locale_t loc);

size_t wcsnrtombs_l(char *restrict dst, const wchar_t **restrict src,
size_t nwc, size_t len, mbstate_t *restrict ps, locale_t loc);

DESCRIPTION


The wcsrtombs() function converts a sequence of wide-characters from the
array indirectly pointed to by src into a sequence of corresponding
characters, beginning in the conversion state described by the object
pointed to by ps. If dst is not a null pointer, the converted characters
are then stored into the array pointed to by dst. Conversion continues up
to and including a terminating null wide-character, which is also
stored. Conversion stops earlier in the following cases:

o When a code is reached that does not correspond to a valid
character.

o When the next character would exceed the limit of len total
bytes to be stored in the array pointed to by dst (and dst is
not a null pointer).

o In the case of wcsnrtombs() and wcsnrtombs_l(), when nwc wide
characters have been completely converted.

Each conversion takes place as if by a call to the wcrtomb() function.

If dst is not a null pointer, the pointer object pointed to by src is
assigned either a null pointer (if conversion stopped due to reaching a
terminating null wide-character) or the address just past the last wide-
character converted (if any). If conversion stopped due to reaching a
terminating null wide-character, the resulting state described is the
initial conversion state.

If ps is a null pointer, these functions uses 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 system will behave as if no function
defined in the Reference Manual calls any of these functions.

The behavior of wcsrtombs() and wcsnrtombs() are affected by the LC_CTYPE
category of the current locale. See environ(7).

The wcsrtombs_l() and wcsnrtombs_l() functions behave identically to
wcsrtombs() and wcsnrtombs() respectively, except that instead of
operating in the current locale, they operate in the locale specified by
loc.

RETURN VALUES


If conversion stops because a code is reached that does not correspond to
a valid character, an encoding error occurs. In this case, these
functions store the value of the macro EILSEQ in errno and return
(size_t)-1; the conversion state is undefined. Otherwise, they return
the number of bytes in the resulting character sequence, not including
the terminating null (if any).

ERRORS


These functions may fail if:

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


EILSEQ
A wide-character code does not correspond to a valid character.

ATTRIBUTES


See attributes(7) for descriptions of the following attributes:

+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | See below. |
+--------------------+-----------------+
|MT-Level | See below. |
+--------------------+-----------------+

The wcsrtombs() and wcsnrtombs() functions are Standard. The
wcsrtombs_l() and wcsnrtombs_l() functions are Uncommitted.

If ps is a null pointer, these functions should be considered Unsafe for
use in multithreaded applications. Otherwise, they are MT-Safe.

SEE ALSO


mbsinit(3C), newlocale(3C), setlocale(3C), uselocale(3C), wcrtomb(3C),
attributes(7), environ(7), standards(7)


July 13, 2014 WCSRTOMBS(3C)