transfer file with tftp

I want to transfer /var/log/messages to the server via tftp protocol.
Server side(tftp is so silly that I have to create a file with exactly the same name and the proper privilege on server side in advance): # touch /tftpboot/messages # chmod a+w /tftpboot/messages       // without granting privilege, tftp client will complain "tftp: server says: Permission denied" while uploading.
Client side: # cd /var/log/ # tftp -pl messages <server ip>
Now, I can cat /tftpboot/messages to check the log message on server.