xref: /netbsd-src/lib/libc/stdio/fgetws.3 (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1.\" $NetBSD: fgetws.3,v 1.1 2003/03/07 07:11:36 tshiozak Exp $
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7.\" Chris Torek and the American National Standards Committee X3,
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38.\"     @(#)fgets.3	8.1 (Berkeley) 6/4/93
39.\"
40.\" Original version ID:
41.\" FreeBSD: src/lib/libc/stdio/fgets.3,v 1.16 2002/05/31 05:01:17 archie Exp
42.\" FreeBSD: src/lib/libc/stdio/fgetws.3,v 1.2 2002/09/06 11:23:55 tjr Exp
43.\"
44.Dd August 6, 2002
45.Dt FGETWS 3
46.Os
47.Sh NAME
48.Nm fgetws
49.Nd get a line of wide characters from a stream
50.Sh LIBRARY
51.Lb libc
52.Sh SYNOPSIS
53.In stdio.h
54.In wchar.h
55.Ft "wchar_t *"
56.Fn fgetws "wchar_t * restrict ws" "int n" "FILE * restrict fp"
57.Sh DESCRIPTION
58The
59.Fn fgetws
60function
61reads at most one less than the number of characters specified by
62.Fa n
63from the given
64.Fa fp
65and stores them in the wide character string
66.Fa ws .
67Reading stops when a newline character is found,
68at end-of-file or error.
69The newline, if any, is retained.
70If any characters are read and there is no error, a
71.Ql \e0
72character is appended to end the string.
73.Sh RETURN VALUES
74Upon successful completion,
75.Fn fgetws
76returns
77.Fa ws .
78If end-of-file occurs before any characters are read,
79.Fn fgetws
80returns
81.Dv NULL
82and the buffer contents remain unchanged.
83If an error occurs,
84.Fn fgetws
85returns
86.Dv NULL
87and the buffer contents are indeterminate.
88The
89.Fn fgetws
90function
91does not distinguish between end-of-file and error, and callers must use
92.Xr feof 3
93and
94.Xr ferror 3
95to determine which occurred.
96.Sh ERRORS
97.Bl -tag -width Er
98.It Bq Er EBADF
99The given
100.Fa fp
101argument is not a readable stream.
102.It Bq Er EILSEQ
103The data obtained from the input stream does not form a valid
104multibyte character.
105.El
106.Pp
107The function
108.Fn fgetws
109may also fail and set
110.Va errno
111for any of the errors specified for the routines
112.Xr fflush 3 ,
113.Xr fstat 2 ,
114.Xr read 2 ,
115or
116.Xr malloc 3 .
117.Sh SEE ALSO
118.Xr feof 3 ,
119.Xr ferror 3 ,
120.Xr fgets 3
121.Sh STANDARDS
122The
123.Fn fgetws
124function
125conforms to
126.St -p1003.1-2001 .
127