xref: /dragonfly/lib/libc/stdio/fgetws.3 (revision f02303f9)
1.\" $NetBSD: fgetws.3,v 1.2 2003/08/07 16:43:23 agc Exp $
2.\" $DragonFly: src/lib/libc/stdio/fgetws.3,v 1.1 2005/07/25 00:37:41 joerg Exp $
3.\"
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7.\" This code is derived from software contributed to Berkeley by
8.\" Chris Torek and the American National Standards Committee X3,
9.\" on Information Processing Systems.
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35.\"     @(#)fgets.3	8.1 (Berkeley) 6/4/93
36.\"
37.\" Original version ID:
38.\" FreeBSD: src/lib/libc/stdio/fgets.3,v 1.16 2002/05/31 05:01:17 archie Exp
39.\" FreeBSD: src/lib/libc/stdio/fgetws.3,v 1.2 2002/09/06 11:23:55 tjr Exp
40.\"
41.Dd August 6, 2002
42.Dt FGETWS 3
43.Os
44.Sh NAME
45.Nm fgetws
46.Nd get a line of wide characters from a stream
47.Sh LIBRARY
48.Lb libc
49.Sh SYNOPSIS
50.In stdio.h
51.In wchar.h
52.Ft "wchar_t *"
53.Fn fgetws "wchar_t * restrict ws" "int n" "FILE * restrict fp"
54.Sh DESCRIPTION
55The
56.Fn fgetws
57function
58reads at most one less than the number of characters specified by
59.Fa n
60from the given
61.Fa fp
62and stores them in the wide character string
63.Fa ws .
64Reading stops when a newline character is found,
65at end-of-file or error.
66The newline, if any, is retained.
67If any characters are read and there is no error, a
68.Ql \e0
69character is appended to end the string.
70.Sh RETURN VALUES
71Upon successful completion,
72.Fn fgetws
73returns
74.Fa ws .
75If end-of-file occurs before any characters are read,
76.Fn fgetws
77returns
78.Dv NULL
79and the buffer contents remain unchanged.
80If an error occurs,
81.Fn fgetws
82returns
83.Dv NULL
84and the buffer contents are indeterminate.
85The
86.Fn fgetws
87function
88does not distinguish between end-of-file and error, and callers must use
89.Xr feof 3
90and
91.Xr ferror 3
92to determine which occurred.
93.Sh ERRORS
94.Bl -tag -width Er
95.It Bq Er EBADF
96The given
97.Fa fp
98argument is not a readable stream.
99.It Bq Er EILSEQ
100The data obtained from the input stream does not form a valid
101multibyte character.
102.El
103.Pp
104The function
105.Fn fgetws
106may also fail and set
107.Va errno
108for any of the errors specified for the routines
109.Xr fflush 3 ,
110.Xr fstat 2 ,
111.Xr read 2 ,
112or
113.Xr malloc 3 .
114.Sh SEE ALSO
115.Xr feof 3 ,
116.Xr ferror 3 ,
117.Xr fgets 3
118.Sh STANDARDS
119The
120.Fn fgetws
121function
122conforms to
123.St -p1003.1-2001 .
124