documented and is incompatible with gnu cp. It has very few good effects
(it recovers some disk space) and many bad ones:
- special files are unlinked after certain errors.
- the data may not be recoverable if the source is a special file or fifo.
- unlinking destroys the target attributes as well as the target data.
- unlinking doesn't actually remove the target data if the target is multiply
linked.
stat the pathname "" in order to decide that the pathname "/" is
a directory. This caused `cp kernel /' to fail if the kernel has
the POSIX behaviour of not allowing the pathname "" to be an alias
for ".". It presumably also caused `cp /etc/motd /' to fail in
the unlikely event that "." is not stat'able.
Be more careful about concatenating pathnames: don't check that
the pathname fits until prefixes have been discarded (the check
was too strict). Print the final pathname in error messages.
Terminate the target directory name properly for error messages.
Don't add a slash between components if there is already a slash.
