Copy FILE to NEWNAME. Both args must be strings.
If NEWNAME names a directory, copy FILE there.
This function always sets the file modes of the output file to match
the input file.
The optional third argument OK-IF-ALREADY-EXISTS specifies what to do
if file NEWNAME already exists. If OK-IF-ALREADY-EXISTS is nil, we
signal a `file-already-exists' error without overwriting. If
OK-IF-ALREADY-EXISTS is a number, we request confirmation from the user
about overwriting; this is what happens in interactive use with M-x.
Any other value for OK-IF-ALREADY-EXISTS means to overwrite the
existing file.
Fourth arg KEEP-TIME non-nil means give the output file the same
last-modified time as the old one. (This works on only some systems.)
A prefix arg makes KEEP-TIME non-nil.
If PRESERVE-UID-GID is non-nil, we try to transfer the
uid and gid of FILE to NEWNAME.
If PRESERVE-SELINUX-CONTEXT is non-nil and SELinux is enabled
on the system, we copy the SELinux context of FILE to NEWNAME.
(fn FILE NEWNAME &optional OK-IF-ALREADY-EXISTS KEEP-TIME PRESERVE-UID-GID PRESERVE-SELINUX-CONTEXT)