mbstowcs(3p) [posix man page]

MBSTOWCS(3P)						     POSIX Programmer's Manual						      MBSTOWCS(3P)

PROLOG

       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

       mbstowcs -- convert a character string to a wide-character string

SYNOPSIS

       #include <stdlib.h>

       size_t mbstowcs(wchar_t *restrict pwcs, const char *restrict s,
	   size_t n);

DESCRIPTION

       The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here
       and the ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.

       The mbstowcs() function shall convert a sequence of characters that begins in the initial shift state from the array pointed to by s into a
       sequence of corresponding wide-character codes and shall store not more than n wide-character codes into the array pointed to by pwcs.	No
       characters  that follow a null byte (which is converted into a wide-character code with value 0) shall be examined or converted. Each char-
       acter shall be converted as if by a call to mbtowc(), except that the shift state of mbtowc() is not affected.

       No more than n elements shall be modified in the array pointed to by pwcs.  If copying takes place between objects that overlap, the behav-
       ior is undefined.

       The  behavior  of  this	function  shall be affected by the LC_CTYPE category of the current locale.  If pwcs is a null pointer, mbstowcs()
       shall return the length required to convert the entire array regardless of the value of n, but no values are stored.

RETURN VALUE

       If an invalid character is encountered, mbstowcs() shall return (size_t)-1 and shall set errno to indicate the error.

       Otherwise, mbstowcs() shall return the number of the array elements modified (or required if pwcs is null), not including a  terminating  0
       code, if any. The array shall not be zero-terminated if the value returned is n.

ERRORS

       The mbstowcs() function shall fail if:

       EILSEQ An invalid byte sequence is detected.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       mblen(), mbtowc(), wctomb(), wcstombs()

       The Base Definitions volume of POSIX.1-2008, <stdlib.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C)  2013  by	the  Institute	of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
       event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Stan-
       dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE
/The Open Group						       2013							      MBSTOWCS(3P)

MBLEN(3P)						     POSIX Programmer's Manual							 MBLEN(3P)

PROLOG

       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

       mblen -- get number of bytes in a character

SYNOPSIS

       #include <stdlib.h>

       int mblen(const char *s, size_t n);

DESCRIPTION

       The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here
       and the ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.

       If  s is not a null pointer, mblen() shall determine the number of bytes constituting the character pointed to by s.  Except that the shift
       state of mbtowc() is not affected, it shall be equivalent to:

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

       The implementation shall behave as if no function defined in this volume of POSIX.1-2008 calls mblen().

       The behavior of this function is affected by the LC_CTYPE category of the current locale. For a	state-dependent  encoding,  this  function
       shall be placed into its initial state by a call for which its character pointer argument, s, is a null pointer. Subsequent calls with s as
       other than a null pointer shall cause the internal state of the function to be altered as necessary. A call with s as a null pointer  shall
       cause  this  function to return a non-zero value if encodings have state dependency, and 0 otherwise. If the implementation employs special
       bytes to change the shift state, these bytes shall not produce separate wide-character codes, but shall be grouped with an adjacent charac-
       ter. Changing the LC_CTYPE category causes the shift state of this function to be unspecified.

       The mblen() function need not be thread-safe.

RETURN VALUE

       If s is a null pointer, mblen() shall return a non-zero or 0 value, if character encodings, respectively, do or do not have state-dependent
       encodings. If s is not a null pointer, mblen() shall either return 0 (if s points to the null byte), or return the  number  of  bytes  that
       constitute  the	character  (if the next n or fewer bytes form a valid character), or return -1 (if they do not form a valid character) and
       may set errno to indicate the error.  In no case shall the value returned be greater than n or the value of the {MB_CUR_MAX} macro.

ERRORS

       The mblen() function may fail if:

       EILSEQ An invalid character sequence is detected.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       mbtowc(), mbstowcs(), wctomb(), wcstombs()

       The Base Definitions volume of POSIX.1-2008, <stdlib.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
       ogy  --	Portable  Operating  System  Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
       event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Stan-
       dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE
/The Open Group						       2013								 MBLEN(3P)