mbtowc — convert a
character to a wide-character code
Standard C Library (libc, -lc)
#include
<stdlib.h>
int
mbtowc(wchar_t * restrict
wcharp, const char * restrict mbchar,
size_t nbytes);
The
mbtowc()
function converts a multibyte character mbchar into a
wide character according to the current conversion state, and stores the
result in the object pointed to by wcharp. Up to
nbytes bytes are examined.
A call with a null mbchar pointer returns
nonzero if the current encoding requires shift states, zero otherwise; if
shift states are required, the shift state is reset to the initial
state.
If mbchar is NULL,
the mbtowc() function returns nonzero if shift
states are supported, zero otherwise.
Otherwise, if mbchar is not a null pointer,
mbtowc() either returns 0 if
mbchar represents the null wide character, or returns
the number of bytes processed in mbchar, or returns -1
if no multibyte character could be recognized or converted. In this case,
mbtowc()'s internal conversion state is
undefined.
The mbtowc() function will fail if:
- [
EILSEQ]
- An invalid multibyte sequence was detected.
- [
EINVAL]
- The internal conversion state is invalid.
The mbtowc() function conforms to
ISO/IEC 9899:1999
(“ISO C99”).