Length of a char array
<p>I have the code like this:</p>

<pre><code>#include &lt;iostream.h&gt;
#include &lt;fstream.h&gt;
void main()
{
    char dir[25], output[10],temp[10];
    cout&lt;&lt;"Enter file: ";
    cin.getline(dir,25);           //like C:\input.txt
    ifstream input(dir,ios::in);
    input.getline(output,'\eof');
    int num = sizeof(output);
    ofstream out("D:\\size.txt",ios::out);
    out&lt;&lt;num;
}
</code></pre>

<p>I want to print the length of the output. But it always returns the number 10 (the given length) even if the input file has only 2 letters ( Like just "ab"). I've also used strlen(output) but nothing changed. How do I only get the used length of array?</p>

<p>I'm using VS C++ 6.0</p>
