Shared Folder Read-only, but Anti-copy

Question

I'm finding a way to prevent a shared folder from being copied by LAN users.
Is there a way for Windows XP ?
If there is any good software out for the purpose, please suggest me.

Solution

By definition, a read only file is able to read and copied from start to EOF but is not able to be written to. If you grant read permissions to a file, you also grant the permission to copy that file's contents to another medium. The only way to prevent the files in question from being copied is to deny read access to the files.

tl;dr

You cannot have files be read only AND not copyable.

Comments

[Eroen]

What you ask is impossible to do by server configuration if the LAN users are supposed to have read access to the shared folder. You might want to redefine your goal as something like "Find a way to limit the amount of data/number of files that can be copied by LAN users".