xref: /freebsd/lib/libc/stdio/fgetws.3 (revision 2008043f386721d58158e37e0d7e50df8095942d)
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32.\"     @(#)fgets.3	8.1 (Berkeley) 6/4/93
33.\" FreeBSD: src/lib/libc/stdio/fgets.3,v 1.16 2002/05/31 05:01:17 archie Exp
34.\"
35.Dd August 6, 2002
36.Dt FGETWS 3
37.Os
38.Sh NAME
39.Nm fgetws
40.Nd get a line of wide characters from a stream
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.In stdio.h
45.In wchar.h
46.Ft "wchar_t *"
47.Fn fgetws "wchar_t * restrict ws" "int n" "FILE * restrict fp"
48.Sh DESCRIPTION
49The
50.Fn fgetws
51function
52reads at most one less than the number of characters specified by
53.Fa n
54from the given
55.Fa fp
56and stores them in the wide character string
57.Fa ws .
58Reading stops when a newline character is found,
59at end-of-file or error.
60The newline, if any, is retained.
61If any characters are read and there is no error, a
62.Ql \e0
63character is appended to end the string.
64.Sh RETURN VALUES
65Upon successful completion,
66.Fn fgetws
67returns
68.Fa ws .
69If end-of-file occurs before any characters are read,
70.Fn fgetws
71returns
72.Dv NULL
73and the buffer contents remain unchanged.
74If an error occurs,
75.Fn fgetws
76returns
77.Dv NULL
78and the buffer contents are indeterminate.
79The
80.Fn fgetws
81function
82does not distinguish between end-of-file and error, and callers must use
83.Xr feof 3
84and
85.Xr ferror 3
86to determine which occurred.
87.Sh ERRORS
88The
89.Fn fgetws
90function will fail if:
91.Bl -tag -width Er
92.It Bq Er EBADF
93The given
94.Fa fp
95argument is not a readable stream.
96.It Bq Er EILSEQ
97The data obtained from the input stream does not form a valid
98multibyte character.
99.El
100.Pp
101The function
102.Fn fgetws
103may also fail and set
104.Va errno
105for any of the errors specified for the routines
106.Xr fflush 3 ,
107.Xr fstat 2 ,
108.Xr read 2 ,
109or
110.Xr malloc 3 .
111.Sh SEE ALSO
112.Xr feof 3 ,
113.Xr ferror 3 ,
114.Xr fgets 3
115.Sh STANDARDS
116The
117.Fn fgetws
118function
119conforms to
120.St -p1003.1-2001 .
121