after issue#23

[yongninglei]

I need to check:

• in func 5, how did the log file copied

-in config, do we really need logdir and tmpdir? maybe do some edit there as well as config.yaml

Need to implement:

Add one flag --check file, only some minor changes

add a check function inside function 5

add a different check function inside function 4, or modulize the check function in createsymlinks