xref: /freebsd/lib/libc/locale/mbsrtowcs.3 (revision 71fe318b852b8dfb3e799cb12ef184750f7f8eac)
1.\" Copyright (c) 2002 Tim J. Robbins
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25.\" $FreeBSD$
26.Dd August 16, 2002
27.Dt MBSRTOWCS 3
28.Os
29.Sh NAME
30.Nm mbsrtowcs
31.Nd "convert a character string to a wide-character string (restartable)"
32.Sh LIBRARY
33.Lb libc
34.Sh SYNOPSIS
35.In wchar.h
36.Ft size_t
37.Fn mbsrtowcs "wchar_t * restrict dst" "const char ** restrict src" "size_t len" "mbstate_t * restrict ps"
38.Sh DESCRIPTION
39The
40.Fn mbsrtowcs
41function converts a sequence of multibyte characters pointed to indirectly by
42.Fa src
43into a sequence of corresponding wide characters and stores at most
44.Fa len
45of them in the
46.Ft wchar_t
47array pointed to by
48.Fa dst ,
49until it encounters a terminating null character ('\e0').
50.Pp
51If
52.Fa dst
53is
54.Dv NULL ,
55no characters are stored.
56.Pp
57If
58.Fa dst
59is not
60.Dv NULL ,
61the pointer pointed to by
62.Fa src
63is updated to point to the character after the one that conversion stopped at.
64If conversion stops because a null character is encountered,
65.No * Ns Fa src
66is set to
67.Dv NULL .
68.Pp
69The
70.Ft mbstate_t
71argument,
72.Fa ps ,
73is used to keep track of the shift state.
74If it is
75.Dv NULL ,
76.Fn mbsrtowcs
77uses an internal, static
78.Ft mbstate_t
79object.
80.Sh RETURN VALUES
81The
82.Fn mbsrtowcs
83function returns the number of wide characters stored in
84the array pointed to by
85.Fa dst
86if successful, otherwise it returns
87.No ( Ns
88.Ft size_t Ns
89.No ) Ns -1 .
90.Sh ERRORS
91The
92.Fn mbsrtowcs
93function will fail if:
94.Bl -tag -width Er
95.It Bq Er EILSEQ
96An invalid multibyte character sequence was encountered.
97.El
98.Sh SEE ALSO
99.Xr mbrtowc 3 ,
100.Xr mbstowcs 3 ,
101.Xr wcsrtombs 3
102.Sh STANDARDS
103The
104.Fn mbsrtowcs
105function conforms to
106.St -isoC-99 .
107.Sh BUGS
108The current implementation does not support shift states.
109