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<H2>wcerr</H2>
<P><B>Library:</B>&nbsp;&nbsp;<A HREF="2-11.html">Input/output</A></P><UL>
<LI><A HREF="#sec1">Local Index</A></LI>
<LI><A HREF="#sec2">Summary</A></LI>
<LI><A HREF="#sec3">Synopsis</A></LI>
<LI><A HREF="#sec4">Description</A></LI>
<LI><A HREF="#sec5">Formatting</A></LI>
<LI><A HREF="#sec6">Example</A></LI>
<LI><A HREF="#sec7">See Also</A></LI>
<LI><A HREF="#sec8">Standards Conformance</A></LI>
</UL>
<A NAME="sec1"><H3>Local Index</H3></A>
No Entries
<A NAME="sec2"><H3>Summary</H3></A>
<P>A predefined stream that controls output to an unbuffered stream buffer associated with the object <SAMP>stderr</SAMP> declared in <SAMP>&lt;cstdio&gt;</SAMP></P>
<A NAME="sec3"><H3>Synopsis</H3></A>

<PRE>#include &lt;iostream&gt;

namespace std {
  extern wostream wcerr;
}
</PRE>
<A NAME="sec4"><H3>Description</H3></A>
<P>The object <SAMP>wcerr</SAMP> controls output to an unbuffered stream buffer associated with the object <SAMP>stderr</SAMP> declared in <SAMP>&lt;cstdio&gt;</SAMP>. By default the standard C and C++ streams are synchronized, but you can improve performance by using the <B><I><A HREF="ios-base.html">ios_base</A></I></B> member function <SAMP>synch_with_stdio</SAMP> to desynchronize them. </P>
<P><SAMP>wcerr</SAMP> uses the locale <SAMP>codecvt</SAMP> facet to convert the wide characters it receives to the tiny characters it outputs to <SAMP>stderr</SAMP>. </P>
<A NAME="sec5"><H3>Formatting</H3></A>
<P>The formatting is done through member functions or manipulators. See <B><I><A HREF="cout.html">cout</A></I></B>, <B><I><A HREF="wcout.html">wcout</A></I></B>, or <B><I><A HREF="basic-ostream.html">basic_ostream</A></I></B>  for details.</P>
<A NAME="sec6"><H3>Example</H3></A>

<UL><PRE>//
// wcerr example
//
#include &lt;iostream&gt;
#include &lt;fstream&gt;

void main ( )
{
  using namespace std;
   
  // open the file "file_name.txt"
  // for reading
  wifstream in("file_name.txt");
  
  // output the all file to stdout
  if ( in ) 
    wcout &lt;&lt; in.rdbuf(); 
  else
    // if the wifstream object is in a bad state
    // output an error message to stderr
    wcerr &lt;&lt; L"Error while opening the file" &lt;&lt; endl;  
}
</PRE></UL>
<A NAME="sec7"><H3>See Also</H3></A>
<P><B><I><A HREF="basic-ostream.html">basic_ostream</A></I></B>, <B><I><A HREF="basic-iostream.html">basic_iostream</A></I></B>, <B><I><A HREF="basic-filebuf.html">basic_filebuf</A></I></B>, <B><I><A HREF="cout.html">cout</A></I></B>, <B><I><A HREF="cin.html">cin</A></I></B>, <B><I><A HREF="cerr.html">cerr</A></I></B>, <B><I><A HREF="clog.html">clog</A></I></B>, <B><I><A HREF="wcin.html">wcin</A></I></B>, <B><I><A HREF="wcout.html">wcout</A></I></B>, <B><I><A HREF="wclog.html">wclog</A></I></B>, <B><I><A HREF="ios-base.html">ios_base</A></I></B>, <B><I><A HREF="basic-ios.html">basic_ios</A></I></B></P>
<A NAME="sec8"><H3>Standards Conformance</H3></A>
<P><I>ISO/IEC 14882:1998 -- International Standard for Information Systems --Programming Language C++, Section 27.3.2</I></P>

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