PRUint32 count;
PRUint32 n, count;
nsresult MetaDataFile::Write(nsIOutputStream* output){    nsresult rv;    PRUint32 count;        rv = output->Write((char*)this, mHeaderSize, &count);    if (NS_FAILED(rv)) return rv;        // write the key to the file.    rv = output->Write(mKey, mKeySize, &count);    if (NS_FAILED(rv)) return rv;        // write the flattened metadata to the file.    if (mMetaDataSize) {        rv = output->Write(mMetaData, mMetaDataSize, &count);        if (NS_FAILED(rv)) return rv;    }        return NS_OK;}