Requests a binlog network stream from the master starting a given position.
You can use SHOW MASTER LOGS to get the current logfile and position from the master.
The master responds either with a
If the binlog-filename is empty, the server will send the binlog-stream of the first known binlog.
request a binlog-stream from the server
1  COM_BINLOG_DUMP 4 binlog-pos 2 flags 4 server-id string[EOF] binlog-filename
binlog_pos (4) -- position in the binlog-file to start the stream with
flags (2) -- can right now has one value:
server_id (4) -- server id of this slave
binlog-filename (string.EOF) -- filename of the binlog on the master