Manual Pages  — MBLEN

mblen – get number of bytes in a character

LIBRARY SYNOPSIS DESCRIPTION RETURN VALUES ERRORS SEE ALSO STANDARDS

Standard C Library (libc, -lc)

#include <stdlib.h>

int
mblen(const char *mbchar, size_t nbytes);

The mblen() function computes the length in bytes of a multibyte character mbchar according to the current conversion state. Up to nbytes bytes are examined.

A call with a null mbchar pointer returns nonzero if the current locale requires shift states, zero otherwise; if shift states are required, the shift state is reset to the initial state.

If mbchar is NULL, the mblen() function returns nonzero if shift states are supported, zero otherwise.

Otherwise, if mbchar is not a null pointer, mblen() 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, mblen()'s internal conversion state is undefined.

The mblen() function will fail if:

[EILSEQ]
	An invalid multibyte sequence was detected.
[EINVAL]
	The internal conversion state is not valid.

The mblen() function conforms to ISO/IEC 9899:1999 ("ISO C99").