NAME
mbsrtowcs,
mbsrtowcs_l, mbsnrtowcs,
mbsnrtowcs_l —
convert a character string to a
wide-character string (restartable)
LIBRARY
library “libc”
SYNOPSIS
#include
<wchar.h>
size_t
mbsrtowcs(wchar_t * restrict
dst, const char ** restrict src,
size_t len, mbstate_t * restrict
ps);
size_t
mbsnrtowcs(wchar_t * restrict
dst, const char ** restrict src,
size_t nms, size_t len,
mbstate_t * restrict ps);
#include
<xlocale.h>
size_t
mbsrtowcs_l(wchar_t * restrict
dst, const char ** restrict src,
size_t len, mbstate_t * restrict
ps, locale_t locale);
size_t
mbsnrtowcs_l(wchar_t * restrict
dst, const char ** restrict src,
size_t nms, size_t len,
mbstate_t * restrict ps, locale_t
locale);
DESCRIPTION
Thembsrtowcs()
and mbsrtowcs_l() functions convert a sequence of
multibyte characters pointed to indirectly by src into a
sequence of corresponding wide characters and store at most
len of them in the wchar_t array
pointed to by dst, until they encounter a terminating
null character ('\0').
If dst is NULL, no
characters are stored.
If dst is not NULL,
the pointer pointed to by src is updated to point to
the character after the one that conversion stopped at. If conversion stops
because a null character is encountered, *src is set
to NULL.
The mbstate_t argument,
ps, is used to keep track of the shift state. If it is
NULL,
mbsrtowcs()
and mbsrtowcs_l() use an internal, static
mbstate_t object, which is initialized to the initial
conversion state at program startup.
The
mbsnrtowcs()
and
mbsnrtowcs_l()
functions behave identically to mbsrtowcs() and
mbsrtowcs_l(), except that conversion stops after
reading at most nms bytes from the buffer pointed to
by src.
The
mbsrtowcs_l()
and
mbsnrtowcs_l()
functions take an explicit locale argument, whereas
the mbsrtowcs() and
mbsnrtowcs() functions use the current global or
per-thread locale.
RETURN VALUES
The mbsrtowcs(),
mbsrtowcs_l(), mbsnrtowcs(),
and mbsnrtowcs_l() functions return the number of
wide characters stored in the array pointed to by dst
if successful, otherwise they return (size_t)-1.
ERRORS
The mbsrtowcs(),
mbsrtowcs_l(), mbsnrtowcs(),
and mbsnrtowcs_l() functions will fail if:
- [
EILSEQ] - An invalid multibyte character sequence was encountered.
- [
EINVAL] - The conversion state is invalid.
SEE ALSO
mbrtowc(3), mbstowcs(3), multibyte(3), wcsrtombs(3), xlocale(3)
STANDARDS
The mbsrtowcs() function conforms to
ISO/IEC 9899:1999
(“ISO C99”).
The mbsrtowcs_l(),
mbsnrtowcs(), and
mbsnrtowcs_l() functions are an extension to the
standard.