Copying[moving] a directory from one volume to another would require traversing a whole directory tree and copying each file and creating copies of each directory [and also deleting these after they are copied]. It is a huge operation in comparison to the rest of the things that File::Copy does.

So I'm not at all surprised that this feature isn't included. Perhaps you don't remember that 'mv' in Unix didn't even handle this case either for many years (we used tar or cpio to do it).

Checking the dependencies for File::Copy I don't see File::Find or some equivalent listed so I'm pretty sure this (significantly more complex case) is not implemented by it.

So I'd actually expect this to be implemented in a separate module that likely uses File::Copy and perhaps File::Path. I don't know if such a module has been written but it seems likely somebody would have done that by now.

According to the docs, it's... not really covered.

    If the destination already exists and is a directory, and the sour
+ce 
    is not a directory, then the source file will be renamed into the
    directory specified by the destination.
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There's a bunch of comments in the module code itself that deals with a broken NFS mount - which at least implies that it should work for moving between mounted dirs. According to my own tests, it does not:

ben@Tyr:/tmp$ mount|grep home
/home on /chroot/home type none (rw,bind)
ben@Tyr:/tmp$ mkdir test; perl -MFile::Copy -we'move("test", "/chroot/
+home/test") or die "test: $!\n"'
mkdir: cannot create directory `test': File exists
test: Is a directory
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It also fails - in a rather ugly manner - when you try to move an existing directory into another existing directory:

ben@Tyr:/tmp$ mkdir test test1; perl -MFile::Copy -we'move("test", "te
+st1") or die "$!\n"'; ls -lR test test1
ls: cannot access test: No such file or directory
test1:
total 0
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In other words, "test" just got wiped out. Not moved, or copied, or even died with an error message - just wiped out. I'd suggest filing a bug report.