1MBSRTOWCS(3P) POSIX Programmer's Manual MBSRTOWCS(3P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 mbsrtowcs - convert a character string to a wide-character string
13 (restartable)
14
16 #include <wchar.h>
17 size_t mbsrtowcs(wchar_t *restrict dst, const char **restrict src,
19 size_t len, mbstate_t *restrict ps);
20
23 The mbsrtowcs() function shall convert a sequence of characters, begin‐
24 ning in the conversion state described by the object pointed to by ps,
25 from the array indirectly pointed to by src into a sequence of corre‐
26 sponding wide characters. If dst is not a null pointer, the converted
27 characters shall be stored into the array pointed to by dst. Conver‐
28 sion continues up to and including a terminating null character, which
29 shall also be stored. Conversion shall stop early in either of the fol‐
30 lowing cases:
31 * A sequence of bytes is encountered that does not form a valid char‐
33 acter.
34 * len codes have been stored into the array pointed to by dst (and dst
36 is not a null pointer).
37 Each conversion shall take place as if by a call to the mbrtowc() func‐
39 tion.
40 If dst is not a null pointer, the pointer object pointed to by src
42 shall be assigned either a null pointer (if conversion stopped due to
43 reaching a terminating null character) or the address just past the
44 last character converted (if any). If conversion stopped due to reach‐
45 ing a terminating null character, and if dst is not a null pointer, the
46 resulting state described shall be the initial conversion state.
47 If ps is a null pointer, the mbsrtowcs() function shall use its own
49 internal mbstate_t object, which is initialized at program start-up to
50 the initial conversion state. Otherwise, the mbstate_t object pointed
51 to by ps shall be used to completely describe the current conversion
52 state of the associated character sequence. The implementation behaves
53 as if no function defined in this volume of IEEE Std 1003.1-2001 calls
54 mbsrtowcs().
55 The behavior of this function shall be affected by the LC_CTYPE cate‐
57 gory of the current locale.
58
60 If the input conversion encounters a sequence of bytes that do not form
61 a valid character, an encoding error occurs. In this case, the mbsr‐
62 towcs() function stores the value of the macro [EILSEQ] in errno and
63 shall return (size_t)-1; the conversion state is undefined. Otherwise,
64 it shall return the number of characters successfully converted, not
65 including the terminating null (if any).
66
68 The mbsrtowcs() function may fail if:
69 EINVAL ps points to an object that contains an invalid conversion
71 state.
72 EILSEQ Invalid character sequence is detected.
74 The following sections are informative.
77
79 None.
80
82 None.
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85 None.
86
88 None.
89
91 mbsinit(), mbrtowc(), the Base Definitions volume of
92 IEEE Std 1003.1-2001, <wchar.h>
93
95 Portions of this text are reprinted and reproduced in electronic form
96 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
97 -- Portable Operating System Interface (POSIX), The Open Group Base
98 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
99 Electrical and Electronics Engineers, Inc and The Open Group. In the
100 event of any discrepancy between this version and the original IEEE and
101 The Open Group Standard, the original IEEE and The Open Group Standard
102 is the referee document. The original Standard can be obtained online
103 at http://www.opengroup.org/unix/online.html .
104IEEE/The Open Group 2003 MBSRTOWCS(3P)