If I understand the question correctly, you already have a tree with some files. Now there is a new changelist and you want your tree to be updated so that only the files listed in this new changelist are synchronized, leaving the rest of the tree intact / unaffected.
If so, then the answer will be - p4 sync @ = changelist. But just to be safe, first try with the p4 sync -n @ = changelist option.
If you try using p4 sync @changelist, you will see that your entire tree is updated / deleted. Just try
p4 sync -n @changelist | more
Ketan jain
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