WCSRTOMBS(3) OpenBSD Programmer's Manual WCSRTOMBS(3)NAMEwcsrtombs - converts a wide-character string to a multibyte character
string (restartable)
SYNOPSIS
#include <stdlib.h>
size_t
wcsrtombs(const char * restrict s, const wchar_t ** restrict pwcs, size_t
n, mbstate_t * restrict ps);
DESCRIPTION
The wcsrtombs() converts the null-terminated wide-character string
indirectly pointed to by pwcs to the corresponding multibyte character
string, and store it to the array pointed to by s. The conversion stops
due to the following reasons:
o The conversion reaches a null wide character. In this case, the null
wide character is also converted.
o The wcsrtombs() has already stored n bytes to the array pointed to by
s.
o The conversion encounters an invalid character.
Each characters will be converted as if wcrtomb(3) is continuously
called, except the internal state of wcrtomb(3) will not be affected.
After conversion, if s is not a NULL pointer, the pointer object pointed
to by pwcs is a NULL pointer (if the conversion is stopped due to
reaching a null wide character) or the first byte of the character just
after the last character converted.
If s is not a null pointer and the conversion is stopped due to reaching
a null wide character, the wcsrtombs() places the state object pointed to
by ps to an initial state after the conversion is taken place.
The behaviour of the wcsrtombs() is affected by the LC_CTYPE category of
the current locale.
These are the special cases:
s == NULL wcsrtombs() returns the number of bytes to store the whole
multibyte character string corresponding to the wide-
character string pointed to by pwcs, not including the
terminating null byte. In this case, n is ignored.
pwcs == NULL || *pwcs == NULL
Undefined (may causes the program to crash).
ps == NULL wcsrtombs() uses its own internal state object to keep the
conversion state, instead of ps mentioned in this manual
page.
Calling any other functions in libc never change the
internal state of wcsrtombs(), that is initialized at
startup time of the program.
RETURN VALUESwcsrtombs() returns:
0 or positive
Number of bytes stored to the array pointed to by s, except
for a null byte. There is no cases that the value returned
is greater than n (unless s is a null pointer). If the
return value is equal to n, the string pointed to by s will
not be null-terminated.
(size_t)-1 pwcs points to the string containing invalid wide
character. The wcsrtombs() also sets errno to indicate the
error.
ERRORSwcsrtombs() may cause an error in the following cases:
[EILSEQ] pwcs points to the string containing an invalid wide
character.
SEE ALSOsetlocale(3), wcrtomb(3), wcstombs(3)STANDARDS
The wcsrtombs() function conforms to ANSI X3.159-1989 (``ANSI C''). The
restrict qualifier is added at ISO/IEC 9899/AMD1:1995 (``ISO C99'').
OpenBSD 4.9 September 10, 2010 OpenBSD 4.9