Write data to a remote file.
int FtpWrite(void *buf, int len, netbuf *nData);
A buffer containing the data to be sent to the remote file.
The number of bytes to be sent from 'buf'.
A handle returned by FtpAccess().
FtpWrite() sends data to a remote file. If the file were accessed in record mode, the necessary conversions are performed.
Returns the number of bytes sent from the user's buffer or -1 on error.