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    <p>Assuming you are using the default global <code>new</code> operator, and have not used the <code>nothrow</code> version of <code>new</code>:</p> <pre><code>int main( int argc, char *argv[] ) { //if new fails, what 'pFile' turns out to be? and do I need to delete //it later? CFileStatic *pFile = new CFileStatic( "Console.h", READ_WRITE ); /* ... */ } </code></pre> <p>There is no "later". In this code, if <code>new</code> fails, it will throw an <code>std::bad_alloc</code> exception, and your program will terminate immediately.</p> <p>Now, if you were to try to handle this situation, you would need to catch that exception. Perhaps like this:</p> <pre><code>int main( int argc, char *argv[] ) { //if new fails, what 'pFile' turns out to be? and do I need to delete //it later? try { CFileStatic *pFile = new CFileStatic( "Console.h", READ_WRITE ); } catch( const std::bad_alloc&amp; ex ) { cout &lt;&lt; "whoops! out of memory." &lt;&lt; ex.what() &lt;&lt; endl; } /* ... */ } </code></pre> <p><code>pFile</code> exists within the scope enclosed by the <code>try</code> block, so it no longer exists. Moving out one level:</p> <pre><code> CFileStatic * pFile = 0; try { pFile = new CFileStatic( "Console.h", READ_WRITE ); } catch( const std::bad_alloc&amp; ex ) { cout &lt;&lt; "whoops! out of memory." &lt;&lt; ex.what() &lt;&lt; endl; } // pFile is still 0 </code></pre> <p><code>pFile</code> is never modified, so the value is unchanged.</p> <hr> <p>Regarding the question of <code>delete</code>ing the pointer. The Standard says (C++03 5.3.5/2):</p> <blockquote> <p>[...] if the value of the operand of delete is the null pointer the operation has no effect.</p> </blockquote> <p>You do not have to delete a NULL pointer, because there is nothing to <code>delete</code>, but doing so will have no effect. You could safely do this:</p> <pre><code>CFileStatic * pFile = 0; try { pFile = new CFileStatic( "Console.h", READ_WRITE ); } catch( const std::bad_alloc&amp; ex ) { cout &lt;&lt; "whoops! out of memory." &lt;&lt; ex.what() &lt;&lt; endl; } delete pFile; // regardless of the success of new, this is OK </code></pre> <p>Note that when doing this, it is especially important that you initialize <code>pFile</code> to the null pointer, as I've done here. If you don't:</p> <pre><code>CFileStatic* pFile; // NO INIT /* ... */ delete pFile; // if new threw, this is undefined behavior </code></pre> <p><code>pFile</code> will still be a garbage pointer. It's not the null pointer, so <code>delete</code> will try to delete it, resulting in Undefined Behavior.</p>
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