Interface of fileRef.
The fileTransfer and fileRef interfaces provide a file transfer service between different computers.
A fileRef object is associated to an original file (origFileName) on a machine (refMachine). It is created by a container (factoryServer) on refMachine, with createFileRef(in string origFileName) method. The fileRef object maintains a list of (machine,filename) for copies. If a copy exists on myMachine, getRef(myMachine) returns the file name of the copy on myMachine, else returns empy string. If there is no copy on myMachine, method getFileTransfer() from container factoryServer on refMachine provides a fileTransfer object dedicated to CORBA file copy. After the copy, addRef(myMachine, localFileNameOnMyMachine) registers the file name of the copy on myMachine.