xref: /freebsd/lib/libc/stdio/fgetws.3 (revision e74101e4eff767325553039def89de70b70f36d3)
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36.\"     @(#)fgets.3	8.1 (Berkeley) 6/4/93
37.\" FreeBSD: src/lib/libc/stdio/fgets.3,v 1.16 2002/05/31 05:01:17 archie Exp
38.\" $FreeBSD$
39.\"
40.Dd August 6, 2002
41.Dt FGETWS 3
42.Os
43.Sh NAME
44.Nm fgetws
45.Nd get a line of wide characters from a stream
46.Sh LIBRARY
47.Lb libc
48.Sh SYNOPSIS
49.In stdio.h
50.In wchar.h
51.Ft "wchar_t *"
52.Fn fgetws "wchar_t *restrict ws" "int n" "FILE *restrict fp"
53.Sh DESCRIPTION
54The
55.Fn fgetws
56function
57reads at most one less than the number of characters specified by
58.Fa n
59from the given
60.Fa fp
61and stores them in the wide character string
62.Fa ws .
63Reading stops when a newline character is found,
64at end-of-file or error.
65The newline, if any, is retained.
66If any characters are read and there is no error, a
67.Ql \e0
68character is appended to end the string.
69.Sh RETURN VALUES
70Upon successful completion,
71.Fn fgetws
72returns
73.Fa ws .
74If end-of-file occurs before any characters are read,
75.Fn fgetws
76returns
77.Dv NULL
78and the buffer contents remain unchanged.
79If an error occurs,
80.Fn fgetws
81returns
82.Dv NULL
83and the buffer contents are indeterminate.
84The
85.Fn fgetws
86function
87does not distinguish between end-of-file and error, and callers must use
88.Xr feof 3
89and
90.Xr ferror 3
91to determine which occurred.
92.Sh ERRORS
93.Bl -tag -width Er
94.It Bq Er EBADF
95The given
96.Fa fp
97argument is not a readable stream.
98.It Bq Er EILSEQ
99The data obtained from the input stream does not form a valid
100multibyte character.
101.El
102.Pp
103The function
104.Fn fgetws
105may also fail and set
106.Va errno
107for any of the errors specified for the routines
108.Xr fflush 3 ,
109.Xr fstat 2 ,
110.Xr read 2 ,
111or
112.Xr malloc 3 .
113.Sh SEE ALSO
114.Xr feof 3 ,
115.Xr ferror 3 ,
116.Xr fgets 3
117.Sh STANDARDS
118The
119.Fn fgetws
120function
121conforms to
122.St -p1003.1-2001 .
123