NAME

mblen, mblen_l - get number of bytes in a character

SYNOPSIS

#include <stdlib.h>
int mblen(const char *s, size_t n);

#include <stdlib.h>
#include <xlocale.h>
int mblen_l(const char *s, size_t n, locale_t loc);

DESCRIPTION

If s is not a null pointer, mblen() and mblen_l() determine the number of bytes constituting the character pointed to by s. The call

: mblen(s, n);

is equivalent to:

: mbtowc((wchar_t *)0, s, n);

A call with s as a null pointer causes this function to return 0.

Whereas the behavior of the mblen() function is affected by the LC_CTYPE category of the current locale, the behavior of mblen_l() is affected by the LC_CTYPE category of the locale specified by loc.

RETURN VALUES

If s is a null pointer, mblen() and mblen_l() returns 0. It s is not a null pointer, mblen() and mblen_l() returns 0 (if s points to the null byte), the number of bytes that constitute the character (if the next n or fewer bytes form a valid character), or −1 (if they do not form a valid character) and may set errno to indicate the error. In no case will the value returned be greater than n or the value of the MB_CUR_MAX macro.

ERRORS

The mblen() and mblen_l() functions may fail if:

EILSEQ

Invalid character sequence is detected.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
CSI	Enabled
Interface Stability	See below.
MT-Level	MT-Safe

The mblen() function is Standard. The mblen_l() function is Uncommitted.