NAME
wcrtomb —
converts a wide character to
a multibyte character (restartable)
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <wchar.h>
size_t
wcrtomb(
char *
restrict s,
wchar_t
wc,
mbstate_t * restrict
ps);
DESCRIPTION
wcrtomb() converts the wide character given by
wc to the corresponding multibyte character, and stores
it in the array pointed to by
s unless
s is a null pointer. This function will modify the first
at most
MB_CUR_MAX
bytes of the array pointed to by
s.
The behaviour of
wcrtomb() is affected by the
LC_CTYPE
category of the current locale.
These are the special cases:
-
-
- wc == 0
- For state-dependent encodings, wcrtomb()
stores a nul byte preceded by special byte sequence (if any) to return to
an initial state in the array pointed to by s, and
the state object pointed to by ps also returns to an
initial state.
-
-
- s == NULL
- wcrtomb() just places
ps into an initial state. It is equivalent to the
following call:
Here, buf is a dummy buffer. In this case,
wc is ignored.
-
-
- ps == NULL
- mbrtowc() uses its own internal state
object to keep the conversion state, instead of ps
mentioned in this manual page.
Calling any other functions in Standard C Library (libc,
-lc) never changes the internal state of
mbrtowc(), which is initialized at startup time of the
program.
RETURN VALUES
wcrtomb() returns:
-
-
- positive
- The number of bytes (including any shift sequences) which
are stored in the array.
-
-
- (size_t)-1
- wc is not a valid wide character. In
this case, wcrtomb() also sets
errno to indicate the error.
ERRORS
wcrtomb() may cause an error in the following case:
-
-
- [
EILSEQ
]
- wc is not a valid wide
character.
-
-
- [
EINVAL
]
- ps points to an invalid or
uninitialized mbstate_t object.
SEE ALSO
setlocale(3),
wctomb(3)
STANDARDS
The
wcrtomb() function conforms to
ISO/IEC
9899/AMD1:1995 (“ISO C90, Amendment 1”). The restrict
qualifier is added at
ISO/IEC 9899:1999
(“ISO C99”).