Rem
        bbdoc: Scans the central header for files.  Returns true if successful.
    End Rem
    Method ScanCentralHeader:Int()
    
        SeekStream(zipFile, 0)
        Local magic_number:Int = ReadInt(zipFile);
        Local zip_start_pos:Int = 0;
        
        ' CRX FILE (Google Chrome Extension File), see: http://developer.chrome.com/extensions/crx.html
        If magic_number = $34327243 Then
            
            zip_start_pos:+4;
            
            ReadInt(zipFile); ' CRX Version
            zip_start_pos:+4;
            
            zip_start_pos:+ReadInt(zipFile); ' length of crx public key
            zip_start_pos:+4;
            
            zip_start_pos:+ReadInt(zipFile); ' length of crx signature
            zip_start_pos:+4;
            
            SeekStream(zipFile, zip_start_pos);
            magic_number:Int = ReadInt(zipFile);
            
        EndIf
        
        ' first check to see if its even a valid ZIP file
        If magic_number <> $04034b50 Then 
            DebugLog("Invalid ZIP file!")
            Return False
        EndIf
        
        Local header_start:Int = 0
        
        ' jump to the end
        SeekStream(zipFile, StreamSize(zipFile) - 4)
        
        ' seek the end central directory structure
        While Not StreamPos(zipFile) = 0
            Local sig:Int = ReadInt(zipFile)
            If sig = $06054b50 Then
                ' jump to start of central dir location    
                SeekStream(zipFile, StreamPos(zipFile) + 12)
                header_start = ReadInt(zipFile)
                Exit                
            Else
                ' rewind 3 bytes and try again
                SeekStream(zipFile, StreamPos(zipFile) - 5)
            EndIf
        EndWhile
    
        ' if we found the header, then process
        If Not header_start Then 
            DebugLog("unable to locate central directory!")
            Return False
        EndIf
        
        header_start:+zip_start_pos;
        
        ' seek to the start of the central directory
        SeekStream(zipFile, header_start)
        
        While True And Not Eof(zipFile)
            Local entry:SZipFileEntry = SZipFileEntry.Create()
            If entry.header.fill(zipFile) Then
                FileList.AddLast(entry)

                ' read filename
                entry.zipFileName = entry.header.FileName            
                extractFilename(entry)                                 
            Else
                Exit
            EndIf
        EndWhile
    
        Return True
    EndMethod