man3/fgetws.3

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   2 .\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
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   4 .\" SPDX-License-Identifier: GPL-2.0-or-later
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   6 .\" References consulted:
   7 .\"   GNU glibc-2 source code and manual
   8 .\"   Dinkumware C library reference http://www.dinkumware.com/
   9 .\"   OpenGroup's Single UNIX specification
  10 .\"     http://www.UNIX-systems.org/online.html
  11 .\"   ISO/IEC 9899:1999
  12 .\"
  13 .\" Modified Tue Oct 16 23:18:40 BST 2001 by John Levon <moz@compsoc.man.ac.uk>
  14 .TH fgetws 3 (date) "Linux man-pages (unreleased)"
  15 .SH NAME
  16 fgetws \- read a wide-character string from a FILE stream
  17 .SH LIBRARY
  18 Standard C library
  19 .RI ( libc ", " \-lc )
  20 .SH SYNOPSIS
  21 .nf
  22 .B #include <wchar.h>
  23 .PP
  24 .BI "wchar_t *fgetws(wchar_t " ws "[restrict ." n "], int " n \
  25 ", FILE *restrict " stream );
  26 .fi
  27 .SH DESCRIPTION
  28 The
  29 .BR fgetws ()
  30 function is the wide-character equivalent
  31 of the
  32 .BR fgets (3)
  33 function.
  34 It reads a string of at most \fIn\-1\fP wide characters into the
  35 wide-character array pointed to by \fIws\fP,
  36 and adds a terminating null wide character (L\[aq]\e0\[aq]).
  37 It stops reading wide characters after it has encountered and
  38 stored a newline wide character.
  39 It also stops when end of stream is reached.
  40 .PP
  41 The programmer must ensure that there is room for at least \fIn\fP wide
  42 characters at \fIws\fP.
  43 .PP
  44 For a nonlocking counterpart, see
  45 .BR unlocked_stdio (3).
  46 .SH RETURN VALUE
  47 The
  48 .BR fgetws ()
  49 function, if successful, returns \fIws\fP.
  50 If end of stream
  51 was already reached or if an error occurred, it returns NULL.
  52 .SH ATTRIBUTES
  53 For an explanation of the terms used in this section, see
  54 .BR attributes (7).
  55 .ad l
  56 .nh
  57 .TS
  58 allbox;
  59 lbx lb lb
  60 l l l.
  61 Interface       Attribute       Value
  62 T{
  63 .BR fgetws ()
  64 T}      Thread safety   MT-Safe
  65 .TE
  66 .hy
  67 .ad
  68 .sp 1
  69 .SH STANDARDS
  70 C11, POSIX.1-2008.
  71 .SH HISTORY
  72 POSIX.1-2001, C99.
  73 .SH NOTES
  74 The behavior of
  75 .BR fgetws ()
  76 depends on the
  77 .B LC_CTYPE
  78 category of the
  79 current locale.
  80 .PP
  81 In the absence of additional information passed to the
  82 .BR fopen (3)
  83 call, it is
  84 reasonable to expect that
  85 .BR fgetws ()
  86 will actually read a multibyte string
  87 from the stream and then convert it to a wide-character string.
  88 .PP
  89 This function is unreliable,
  90 because it does not permit to deal properly with
  91 null wide characters that may be present in the input.
  92 .SH SEE ALSO
  93 .BR fgetwc (3),
  94 .BR unlocked_stdio (3)