stdio/fgetws.3

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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: src/lib/libc/stdio/fgetws.3,v 1.3 2003/03/09 02:56:54 tjr Exp $
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  40 .Dd August 6, 2002
  41 .Dt FGETWS 3
  42 .Os
  43 .Sh NAME
  44 .Nm fgetws ,
  45 .Nm fgetws_l
  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 .Fo fgetws
  54 .Fa "wchar_t *restrict ws"
  55 .Fa "int n"
  56 .Fa "FILE *restrict stream"
  57 .Fc
  58 .In stdio.h
  59 .In wchar.h
  60 .In xlocale.h
  61 .Ft "wchar_t *"
  62 .Fo fgetws_l
  63 .Fa "wchar_t *restrict ws"
  64 .Fa "int n"
  65 .Fa "FILE *restrict stream"
  66 .Fa "locale_t loc"
  67 .Fc
  68 .Sh DESCRIPTION
  69 The
  70 .Fn fgetws
  71 function
  72 reads at most one less than the number of characters specified by
  73 .Fa n
  74 from the given
  75 .Fa stream
  76 and stores them in the wide character string
  77 .Fa ws .
  78 Reading stops when a newline character is found,
  79 at end-of-file or error.
  80 The newline, if any, is retained.
  81 If any characters are read and there is no error, a
  82 .Ql \e0
  83 character is appended to end the string.
  84 .Pp
  85 While the
  86 .Fn fgetws
  87 function uses the current locale, the
  88 .Fn fgetws_l
  89 function may be passed a locale directly. See
  90 .Xr xlocale 3
  91 for more information.
  92 .Sh RETURN VALUES
  93 Upon successful completion,
  94 .Fn fgetws
  95 returns
  96 .Fa ws .
  97 If end-of-file occurs before any characters are read,
  98 .Fn fgetws
  99 returns
 100 .Dv NULL
 101 and the buffer contents remain unchanged.
 102 If an error occurs,
 103 .Fn fgetws
 104 returns
 105 .Dv NULL
 106 and the buffer contents are indeterminate.
 107 The
 108 .Fn fgetws
 109 function
 110 does not distinguish between end-of-file and error;
 111 callers must use
 112 .Xr feof 3
 113 and
 114 .Xr ferror 3
 115 to determine which occurred.
 116 .Sh ERRORS
 117 The
 118 .Fn fgetws
 119 function will fail if:
 120 .Bl -tag -width Er
 121 .It Bq Er EBADF
 122 The given
 123 .Fa stream
 124 argument is not a readable stream.
 125 .It Bq Er EILSEQ
 126 The data obtained from the input stream does not form a valid
 127 multibyte character.
 128 .El
 129 .Pp
 130 The function
 131 .Fn fgetws
 132 may also fail and set
 133 .Va errno
 134 for any of the errors specified for the routines
 135 .Xr fflush 3 ,
 136 .Xr fstat 2 ,
 137 .Xr read 2 ,
 138 or
 139 .Xr malloc 3 .
 140 .Sh SEE ALSO
 141 .Xr feof 3 ,
 142 .Xr ferror 3 ,
 143 .Xr fgets 3 ,
 144 .Xr xlocale 3
 145 .Sh STANDARDS
 146 The
 147 .Fn fgetws
 148 function
 149 conforms to
 150 .St -p1003.1-2001 .