stdio/FreeBSD/fgetws.3

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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 .\" $FreeBSD: src/lib/libc/stdio/fgetws.3,v 1.4 2007/01/09 00:28:06 imp Exp $
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  36 .Dd August 6, 2002
  37 .Dt FGETWS 3
  38 .Os
  39 .Sh NAME
  40 .Nm fgetws ,
  41 .Nm fgetws_l
  42 .Nd get a line of wide characters from a stream
  43 .Sh LIBRARY
  44 .Lb libc
  45 .Sh SYNOPSIS
  46 .In stdio.h
  47 .In wchar.h
  48 .Ft "wchar_t *"
  49 .Fo fgetws
  50 .Fa "wchar_t *restrict ws"
  51 .Fa "int n"
  52 .Fa "FILE *restrict stream"
  53 .Fc
  54 .In stdio.h
  55 .In wchar.h
  56 .In xlocale.h
  57 .Ft "wchar_t *"
  58 .Fo fgetws_l
  59 .Fa "wchar_t *restrict ws"
  60 .Fa "int n"
  61 .Fa "FILE *restrict stream"
  62 .Fa "locale_t loc"
  63 .Fc
  64 .Sh DESCRIPTION
  65 The
  66 .Fn fgetws
  67 function
  68 reads at most one less than the number of characters specified by
  69 .Fa n
  70 from the given
  71 .Fa stream
  72 and stores them in the wide character string
  73 .Fa ws .
  74 Reading stops when a newline character is found,
  75 at end-of-file or error.
  76 The newline, if any, is retained.
  77 If any characters are read and there is no error, a
  78 .Ql \e0
  79 character is appended to end the string.
  80 .Pp
  81 While the
  82 .Fn fgetws
  83 function uses the current locale, the
  84 .Fn fgetws_l
  85 function may be passed a locale directly. See
  86 .Xr xlocale 3
  87 for more information.
  88 .Sh RETURN VALUES
  89 Upon successful completion,
  90 .Fn fgetws
  91 returns
  92 .Fa ws .
  93 If end-of-file occurs before any characters are read,
  94 .Fn fgetws
  95 returns
  96 .Dv NULL
  97 and the buffer contents remain unchanged.
  98 If an error occurs,
  99 .Fn fgetws
 100 returns
 101 .Dv NULL
 102 and the buffer contents are indeterminate.
 103 The
 104 .Fn fgetws
 105 function
 106 does not distinguish between end-of-file and error;
 107 callers must use
 108 .Xr feof 3
 109 and
 110 .Xr ferror 3
 111 to determine which occurred.
 112 .Sh ERRORS
 113 The
 114 .Fn fgetws
 115 function will fail if:
 116 .Bl -tag -width Er
 117 .It Bq Er EBADF
 118 The given
 119 .Fa stream
 120 argument is not a readable stream.
 121 .It Bq Er EILSEQ
 122 The data obtained from the input stream does not form a valid
 123 multibyte character.
 124 .El
 125 .Pp
 126 The function
 127 .Fn fgetws
 128 may also fail and set
 129 .Va errno
 130 for any of the errors specified for the routines
 131 .Xr fflush 3 ,
 132 .Xr fstat 2 ,
 133 .Xr read 2 ,
 134 or
 135 .Xr malloc 3 .
 136 .Sh SEE ALSO
 137 .Xr feof 3 ,
 138 .Xr ferror 3 ,
 139 .Xr fgets 3 ,
 140 .Xr xlocale 3
 141 .Sh STANDARDS
 142 The
 143 .Fn fgetws
 144 function
 145 conforms to
 146 .St -p1003.1-2001 .