mbrtowc(3) [linux man page]

MBRTOWC(3)						     Linux Programmer's Manual							MBRTOWC(3)

NAME

       mbrtowc - convert a multibyte sequence to a wide character

SYNOPSIS

       #include <wchar.h>

       size_t mbrtowc(wchar_t *pwc, const char *s, size_t n, mbstate_t *ps);

DESCRIPTION

       The  main  case for this function is when s is not NULL and pwc is not NULL.  In this case, the mbrtowc() function inspects at most n bytes
       of the multibyte string starting at s, extracts the next complete multibyte character, converts it to a wide character  and  stores  it	at
       *pwc.   It  updates  the  shift state *ps.  If the converted wide character is not L'', it returns the number of bytes that were consumed
       from s.	If the converted wide character is L'', 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, mbrtowc() 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, mbrtowc() returns
       (size_t) -1 and sets errno to EILSEQ.  In this case, the effects on *ps are undefined.

       A different case is when s is not NULL but pwc is NULL.	In this case the mbrtowc() function behaves as above,  except  that  it  does  not
       store the converted wide character in memory.

       A  third  case  is  when s is NULL.  In this case, pwc and n are ignored.  If the conversion state represented by *ps denotes an incomplete
       multibyte character conversion, the mbrtowc() function returns (size_t) -1, sets errno to EILSEQ, and leaves *ps  in  an  undefined  state.
       Otherwise, the mbrtowc() function puts *ps in the initial state and returns 0.

       In  all	of  the above cases, if ps is a NULL pointer, a static anonymous state only known to the mbrtowc function is used instead.  Other-
       wise, *ps must be a valid mbstate_t object.  An mbstate_t object a can be initialized to the initial state by zeroing it, for example using

	   memset(&a, 0, sizeof(a));

RETURN VALUE

       The mbrtowc() function returns the number of bytes parsed from the multibyte sequence starting at s, if a non-L'' wide character was rec-
       ognized.  It returns 0, if a L'' 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.

CONFORMING TO

       C99.

NOTES

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

SEE ALSO

       mbsrtowcs(3)

COLOPHON

       This page is part of release 3.27 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/.

GNU
								    2001-11-22								MBRTOWC(3)

MBRTOWC(3)						     Linux Programmer's Manual							MBRTOWC(3)

NAME

       mbrtowc - convert a multibyte sequence to a wide character

SYNOPSIS

       #include <wchar.h>

       size_t mbrtowc(wchar_t *pwc, const char *s, size_t n, mbstate_t *ps);

DESCRIPTION

       The  main  case for this function is when s is not NULL and pwc is not NULL.  In this case, the mbrtowc() function inspects at most n bytes
       of the multibyte string starting at s, extracts the next complete multibyte character, converts it to a wide character  and  stores  it	at
       *pwc.   It  updates  the  shift state *ps.  If the converted wide character is not L'', it returns the number of bytes that were consumed
       from s.	If the converted wide character is L'', 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, mbrtowc() 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, mbrtowc() returns
       (size_t) -1 and sets errno to EILSEQ.  In this case, the effects on *ps are undefined.

       A different case is when s is not NULL but pwc is NULL.	In this case the mbrtowc() function behaves as above,  except  that  it  does  not
       store the converted wide character in memory.

       A  third  case  is  when s is NULL.  In this case, pwc and n are ignored.  If the conversion state represented by *ps denotes an incomplete
       multibyte character conversion, the mbrtowc() function returns (size_t) -1, sets errno to EILSEQ, and leaves *ps  in  an  undefined  state.
       Otherwise, the mbrtowc() function puts *ps in the initial state and returns 0.

       In  all	of  the above cases, if ps is a NULL pointer, a static anonymous state only known to the mbrtowc function is used instead.  Other-
       wise, *ps must be a valid mbstate_t object.  An mbstate_t object a can be initialized to the initial state by zeroing it, for example using

	   memset(&a, 0, sizeof(a));

RETURN VALUE

       The mbrtowc() function returns the number of bytes parsed from the multibyte sequence starting at s, if a non-L'' wide character was rec-
       ognized.  It returns 0, if a L'' 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.

CONFORMING TO

       C99.

NOTES

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

SEE ALSO

       mbsrtowcs(3)

COLOPHON

       This page is part of release 3.25 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/.

GNU
								    2001-11-22								MBRTOWC(3)