i want to copy files from 172.16.1.6/data/ to
my system (172.17.1.4/dat/) .but only those files
which we have not copied previously.

we should use scp in perl


Hello.   Can you describe the problems that you're having in trying to write this script - perhaps post up some code so that we can give you some specific advise?  Have a look at our Posting FAQ which gives you suggestions in how to make the best use of resources here.

You have marked your post "most urgent".  I see all questions posted here within 24 hours, and respond as soon as is practical for me.  I don't have infinite resources for this service so I tend to put more time into questions that follow the FAQ - that's far more efficient for all concerned.  Posting out of the blue something marked as urgent is something the FAQ explicity asks you not to do (it explains why), and it won't get better or quicker answers I'm afraid.



You sound like your in need of 'rsync'
Code:

DESCRIPTION       rsync is a program that behaves in much the same way that rcp does, but       has many more options and uses  the  rsync  remote-update  protocol  to       greatly  speed  up  file  transfers  when  the destination file already       exists.       The rsync remote-update protocol allows rsync to transfer just the dif-       ferences between two sets of files across the network connection, using       an efficient  checksum-search  algorithm  described  in  the  technical       report that accompanies this package.

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