write_chars
Description:
public IOStatus write_chars (char[] buf, out size_t bytes_written) throws ConvertError, IOChannelError
  
  Replacement for g_io_channel_write with the new API.
On seekable channels with encodings other than null or UTF-8, generic mixing of reading and writing is not allowed. A call to g_io_channel_write_chars () may only be made on a channel from which data has been read in the cases described in the documentation for g_io_channel_set_encoding ().
Parameters:
| this | |
| buf | a buffer to write data from | 
| bytes_written | The number of bytes written. This can be nonzero  even if the return value is not g_io_status_normal.  
            If the return value is g_io_status_normal and the  channel is blocking, this will always be equal  to 
             | 
| count | the size of the buffer. If -1, the buffer is taken to be a nul-terminated string. | 
Returns:
| the status of the operation. |