MBRLEN(3)

NAME
mbrlen - determine number of bytes in next multibyte character

SYNOPSIS
#include <wchar.h>

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

DESCRIPTION
The mbrlen() function inspects at most n bytes of the multibyte string starting at s and extracts the next complete multibyte character. It updates the shift state *ps. If the multibyte character is not the null wide character, it returns the number of bytes that were consumed from s. If the multibyte character is the null wide character, it resets the shift state *ps to the initial state and returns 0.

If the n bytes starting at s do not contain a complete multibyte character, mbrlen() returns (size_t) -2. This can happen even if n >= MB_CUR_MAX, if the multibyte string contains redundant shift sequences.

If the multibyte string starting at s contains an invalid multibyte sequence before the next complete character, mbrlen() returns (size_t) -1 and sets errno to EILSEQ. In this case, the effects on *ps are undefined.

If ps is NULL, a static anonymous state known only to the mbrlen() function is used instead.

RETURN VALUE
The mbrlen() function returns the number of bytes parsed from the multibyte sequence starting at s, if a non-null wide character was recognized. It returns 0, if a null wide character was recognized. It returns (size_t) -1 and sets errno to EILSEQ, if an invalid multibyte sequence was encountered. It returns (size_t) -2 if it couldn't parse a complete multibyte character, meaning that n should be increased.

ATTRIBUTES

  Multithreading (see pthreads(7))
The mbrlen() function is thread-safe with exceptions. It is not thread-safe if called with a NULL ps parameter.

CONFORMING TO
C99.

NOTES
The behavior of mbrlen() depends on the LC_CTYPE category of the current locale.

SEE ALSO
mbrtowc(3)

COLOPHON
This page is part of release 3.57 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.