Determines the number of bytes comprising a multibyte character.

    Format

      #include  <wchar.h>

      size_t mbrlen  (const char *s, size_t n, mbstate_t *ps);

1  –  Arguments

 s

    A pointer to a multibyte character.

 n

    The maximum number of bytes that comprise the multibyte
    character.

 ps

    A pointer to the mbstate_t object. If a NULL pointer is
    specified, the function uses its internal mbstate_t object.
    mbstate_t is an opaque datatype intended to keep the conversion
    state for the state-dependent codesets.

2  –  Description

    The mbrlen function is equivalent to the call:

        mbrtowc(NULL, s, n, ps != NULL ? ps : &internal)

    Where internal is the mbstate_t object for the mbrlen function.

    If the multibyte character pointed to by s is of n bytes or less,
    the function returns the number of bytes comprising the character
    (including any shift sequences).

    If either an encoding error occurs or the next n bytes contribute
    to an incomplete but potentially valid multibyte character, the
    function returns -1 or -2, respectively.

    See also mbrtowc.

3  –  Return Values

    x                  The number of bytes comprising the multibyte
                       character.
    0                  Indicates that s is a NULL pointer or a
                       pointer to a null byte.
    -1                 Indicates an encoding error, in which case
                       the next n or fewer bytes do not contribute
                       to a complete and valid multibyte character.
                       errno is set to EILSEQ; the conversion state
                       is undefined.
    -2                 Indicates an incomplete but potentially valid
                       multibyte character (all n bytes have been
                       processed).