C++ expected primary-expression before char (header file)
<p>ISBN.h  </p>

<pre><code>int isValid(const char str[]);
int isRegistered(FILE* fp, const char str[], char area[], char publisher[], char title[]); 
</code></pre>

<p>error: </p>

<pre><code>ISBN.h:2:18: error: FILE was not declared in this scope
ISBN.h:2:24: error: fp was not declared in this scope
ISBN.h:2:28: error: expected primary-expression before const
ISBN.h:2:46: error: expected primary-expression before char
ISBN.h:2:59: error: expected primary-expression before char
ISBN.h:2:77: error: expected primary-expression before char
ISBN.h:2:89: error: expression list treated as compound expression in initializer [-fpermissive]   
</code></pre>

<p>Not sure I understand the error as I have another header file with the same sort of parameters that doesn't yield any errors:  </p>

<p>ISBNPrefix.h  </p>

<pre><code>FILE* open(const char filename[]);
int isRegistered(FILE* fp, int area);
int minNoDigits(FILE* fp, int area);
int isRegistered(FILE* fp, int area, const char publisher[]);
int close(FILE* fp);
</code></pre>

<ol>
<li>These function prototypes are given to us by our professor.</li>
<li><code>isRegistered</code> is defined three times but with a different amount of paramaters, so when you use the function in <code>main</code> with X amount of parameters, will it just use the corresponding version with said parameters? </li>
<li><p>I get a second set of errors corresponding to my <code>ISBN.cpp</code> which includes my <code>ISBN.h</code>:  </p>

<p>ISBN.cpp: In function int isRegistered(FILE*, const char*, char*, char*, char*):
ISBN.cpp:36:89: error: int isRegistered(FILE*, const char*, char*, char*, char*) redeclared as different kind of symbol
ISBN.h:2:5: error: previous declaration of int isRegistered  </p></li>
</ol>

<p>ISBN.cpp</p>

<pre><code>#include "ISBN.h"
#include &lt;cstring&gt;
#include &lt;iostream&gt;
#include &lt;cstdio&gt;
using namespace std;

int isValid(const char str[])
{

}

int isRegistered(FILE* fp, const char str[], char area[], char publisher[], char title[])
{

} 
</code></pre>
