Originální popis anglicky:
wctomb - convert a wide-character code to a character
Návod, kniha: POSIX Programmer's Manual
#include <stdlib.h>
int wctomb(char *
s, wchar_t
wchar );
The
wctomb() function shall determine the number of bytes needed to
represent the character corresponding to the wide-character code whose value
is
wchar (including any change in the shift state). It shall store the
character representation (possibly multiple bytes and any special bytes to
change shift state) in the array object pointed to by
s (if
s is
not a null pointer). At most {MB_CUR_MAX} bytes shall be stored. If
wchar is 0, a null byte shall be stored, preceded by any shift sequence
needed to restore the initial shift state, and
wctomb() shall be left
in the initial shift state.
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.
Changing the
LC_CTYPE category causes the shift state of this function
to be unspecified.
The
wctomb() function need not be reentrant. A function that is not
required to be reentrant is not required to be thread-safe.
The implementation shall behave as if no function defined in this volume of
IEEE Std 1003.1-2001 calls
wctomb().
If
s is a null pointer,
wctomb() 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,
wctomb() shall return -1
if the value of
wchar does not correspond to a valid character, or
return the number of bytes that constitute the character corresponding to the
value of
wchar.
In no case shall the value returned be greater than the value of the
{MB_CUR_MAX} macro.
No errors are defined.
The following sections are informative.
None.
None.
None.
None.
mblen() ,
mbtowc() ,
mbstowcs() ,
wcstombs() , the
Base Definitions volume of IEEE Std 1003.1-2001,
<stdlib.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. 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 Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html
.
