1MBTOWC(3) Linux Programmer's Manual MBTOWC(3)
2
3
4
6 mbtowc - convert a multibyte sequence to a wide character
7
9 #include <stdlib.h>
10
11 int mbtowc(wchar_t *pwc, const char *s, size_t n);
12
14 The main case for this function is when s is not NULL and pwc is not
15 NULL. In this case, the mbtowc() function inspects at most n bytes of
16 the multibyte string starting at s, extracts the next complete multi‐
17 byte character, converts it to a wide character and stores it at *pwc.
18 It updates an internal shift state only known to the mbtowc function.
19 If s does not point to a '\0' byte, it returns the number of bytes that
20 were consumed from s, otherwise it returns 0.
21
22 If the n bytes starting at s do not contain a complete multibyte char‐
23 acter, or if they contain an invalid multibyte sequence, mbtowc()
24 returns -1. This can happen even if n >= MB_CUR_MAX, if the multibyte
25 string contains redundant shift sequences.
26
27 A different case is when s is not NULL but pwc is NULL. In this case
28 the mbtowc() function behaves as above, except that it does not store
29 the converted wide character in memory.
30
31 A third case is when s is NULL. In this case, pwc and n are ignored.
32 The mbtowc() function resets the shift state, only known to this func‐
33 tion, to the initial state, and returns non-zero if the encoding has
34 nontrivial shift state, or zero if the encoding is stateless.
35
37 If s is not NULL, the mbtowc() function returns the number of consumed
38 bytes starting at s, or 0 if s points to a null byte, or -1 upon fail‐
39 ure.
40
41 If s is NULL, the mbtowc() function returns non-zero if the encoding
42 has nontrivial shift state, or zero if the encoding is stateless.
43
45 C99.
46
48 The behavior of mbtowc() depends on the LC_CTYPE category of the cur‐
49 rent locale.
50
51 This function is not multithread safe. The function mbrtowc(3) pro‐
52 vides a better interface to the same functionality.
53
55 MB_CUR_MAX(3), mbrtowc(3), mbstowcs(3)
56
58 This page is part of release 3.22 of the Linux man-pages project. A
59 description of the project, and information about reporting bugs, can
60 be found at http://www.kernel.org/doc/man-pages/.
61
62
63
64GNU 2001-07-04 MBTOWC(3)