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The C++ Debugging Support Library
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By Carlo Wood, ©1999 - 2003.
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<H2>Tutorial 3: Setting the <CODE>ostream</CODE></H2>
<P>You can write the debug output to any given ostream.
The following example opens a file <SPAN class="filename">log</SPAN> and
uses it to write its debug output to.</P>
<P class="download">[<A HREF="log_file.cc">download</A>]</P>
<P>Compile as: <CODE>g++ -DCWDEBUG log_file.cc -lcwd -o log_file</CODE></P>
<PRE>
#include "sys.h" // See tutorial 2.
#include <fstream>
#include "debug.h" // See tutorial 2.
int main(void)
{
Debug( dc::notice.on() );
Debug( libcw_do.on() );
#ifdef CWDEBUG
std::ofstream file;
file.open("log");
#endif
// Set the ostream related with libcw_do to `file':
<SPAN class="highlight">Debug( libcw_do.set_ostream(&file) );</SPAN>
Dout(dc::notice, "Hippopotamus are heavy");
return 0;
}
</PRE>
<P>Debug code like the definition of the debug file <CODE>file</CODE>,
should be put between <CODE>#ifdef CWDEBUG ... #endif</CODE> as usual.
This isn't needed for <CODE>Debug()</CODE> or <CODE>Dout()</CODE>
because these macros are automatically replaced with white space
when <CODE>CWDEBUG</CODE> is not defined.</P>
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<ADDRESS>Copyright © 2001, 2002 Carlo Wood. All rights reserved.</ADDRESS>
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