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POReturning ifstream in a function
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  1. POReturning ifstream in a function
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    copied!<p>Here's probably a very noobish question for you: How (if at all possible) can I return an ifstream from a function?</p> <p>Basically, I need to obtain the filename of a database from the user, and if the database with that filename does not exist, then I need to create that file for the user. I know how to do that, but only by asking the user to restart the program after creating the file. I wanted to avoid that inconvenience for the user if possible, but the function below does not compile in gcc:</p> <pre><code>ifstream getFile() { string fileName; cout &lt;&lt; "Please enter in the name of the file you'd like to open: "; cin &gt;&gt; fileName; ifstream first(fileName.c_str()); if(first.fail()) { cout &lt;&lt; "File " &lt;&lt; fileName &lt;&lt; " not found.\n"; first.close(); ofstream second(fileName.c_str()); cout &lt;&lt; "File created.\n"; second.close(); ifstream third(fileName.c_str()); return third; //compiler error here } else return first; } </code></pre> <p>EDIT: sorry, forgot to tell you where and what the compiler error was:</p> <pre><code>main.cpp:45: note: synthesized method ‘std::basic_ifstream&lt;char, std::char_traits&lt;char&gt; &gt;::basic_ifstream(const std::basic_ifstream&lt;char, std::char_traits&lt;char&gt; &gt;&amp;)’ first required here </code></pre> <p>EDIT: I changed the function to return a pointer instead as Remus suggested, and changed the line in main() to "ifstream database = *getFile()"; now I get this error again, but this time in the line in main():</p> <pre><code>main.cpp:27: note: synthesized method ‘std::basic_ifstream&lt;char, std::char_traits&lt;char&gt; &gt;::basic_ifstream(const std::basic_ifstream&lt;char, std::char_traits&lt;char&gt; &gt;&amp;)’ first required here </code></pre>
 

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