mbsrtowcs()

convert multibyte character string to wide characters 

Function

SYNOPSIS

#include <wchar.h>

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

DESCRIPTION

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

Each conversion takes place as if by a call to the mbrtowc() 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 character) or the address just past the last character converted (if any). If conversion stopped due to reaching a terminating null character and dst is not a null pointer, the resulting state described is the initial conversion state.

If the specified state pointer is null, the mbsrtowcs() function uses its own internal mbstate_t object, which is initialized at program startup to the initial conversion state. Otherwise, the specified mbstate_t object is used to completely describe the current conversion state of the associated character sequence.

The behavior of this function is affected by the LC_CTYPE category of the current locale.

PARAMETERS

dst 

Destination buffer to receive converted characters. This can be a null pointer if no conversion is desired.

src 

Pointer to the string to be converted. If dst is not null, the referenced pointer is updated as described above.

len 

Maximum number of wide characters to write to dst, if dst is not null.

ps 

Conversion state. If this is null, an internal mbstate_t object is used.

RETURN VALUES

If the input conversion encounters a sequence of bytes that do not form a valid character, an encoding error occurs. In this case, the mbsrtowcs() function sets errno to EILSEQ and returns -1; the conversion state is undefined. Otherwise, it returns the number of characters successfully converted, not including the terminating null (if any).

CONFORMANCE

ANSI/ISO 9899-1990/AM 1-1995

MULTITHREAD SAFETY LEVEL

MT-Safe, with exceptions.

This function is MT-Safe as long as no thread calls setlocale() while this function is executing and the 'ps' parameter is non-NULL.

PORTING ISSUES

None.

AVAILABILITY

MKS Toolkit for Professional Developers
MKS Toolkit for Enterprise Developers
MKS Toolkit for Enterprise Developers 64-Bit Edition

SEE ALSO

Functions:
mbrlen(), mbrtowc(), mbsinit(), setlocale(), wcrtomb(), wcsrtombs()

MKS Toolkit 9.3 Documentation Build 6.