Editing File copying (section)

== Remote copy ==
{{anchor|NCOPY}}
Some systems have specialized [[system call]]s for copying files (like {{code|CopyFile}} in [[Windows API]]), while others (like Unix-based and DOS) simply read the contents of the existing file into memory and write it to a new file. A specialized system call provides little advantage for files on local [[computer storage|storage]], but can optimize operation when the source and target files are on a remote [[file server]]. The system call can tell the server to process the files on the server's file system; without sending file content over the network; thus greatly improving performance. Lacking such file server support, copying requires reading file content over the network, and sending it back over the network again. 

Sometimes, remote file copying is performed with a specialized command, like {{code|NCOPY}} in DOS clients for [[Novell NetWare]]. The [[COPY (DOS command)|COPY]] command in some versions of [[DR-DOS]] since 1992,<ref name="Caldera_1997_DOSSRC"/> has built-in support for this.
An even more complicated situation arises when one needs to copy files between two remote servers. The simple way is to read data from one server, and then to write the data to the second server.