Re: cp command will copy to subdirectory without appending /

[Todd Partridge]

On Tue, Oct 20, 2009 at 12:59 AM, Bob Proulx <bob@proulx.com> wrote:
> Todd Partridge wrote:
>> The cp command will copy to a subdirectory without an appending /
>
> You have reached bug-bash, not bug-coreutils.  The 'cp' program is in
> the GNU Coreutils project and so bug reports for 'cp' should go to
> bug-coreutils@gnu.org and not to bug-bash.  The bug-bash list is for
> bugs and discussion about bash.
>
>> mkdir test test2
>> touch abc test
>> touch bcd test2
>
> I think you have typed this in incorrectly.  That produces:
>
>  ./abc
>  ./bcd
>  ./test
>  ./test2

Yes, I did.  The correct syntax, would be:

mkdir test test2
touch abc test/
touch bcd test2/

>
>> cp -R test2 test
>
> Because test is a directory test2 will be copied into that directory.
> With the above that produces:
>
>  ./abc
>  ./bcd
>  ./test
>  ./test/test2
>  ./test2
>
>> ls test
>> test2 abc
>
> That result cannot be produced from the given commands.  Please
> rephrase the question.

? I was tired last night :), the good typing would be:

ls test/
test2  abc

>
>> Since the cp command can also rename
>
> I think you misunderstand how cp works.  A quick and casual summary
> here.  If the target is not a directory then the source file
> (singular) is copied to the destination.  If the target is a directory
> then cp copies the source files (one or more) into the destination
> directory.  If the target has an appended '/' then the destination
> must be a directory.

Because the cp command also renames, I understand the default behavior
to assume that you want to cp.  But I believe the default behavior to
assume a directory 'test/'  when typing 'test' would lead to more
problems for advanced users.  Feedback that 'directory already exists'
I think would be a more direct behavior.  Hmm.

>
> Here is the full standards document:
>
>  http://www.opengroup.org/onlinepubs/009695399/utilities/cp.html
>
>> I think the proper behavior here for 'cp -R test2 test' would be to
>> error and print that 'Folder already exists'.
>
> Of course that would break decades of scripts which expect the
> standard behavior.  I don't understand why would you change this long
> standing useful behavior.  Could you say a few words more about what
> your problem is with the current behavior?

Yeah, well there is little doubt that this would break things :).  For
advanced users I would actually see this as a benefit though we
probably are all responsible for the occasional forgetting of
appending a backslash.

>
>> Appending a / would imply the directory:
>> cp -R test2 test/
>> This usage will remove the ambiguity of the command between the copy
>> function and the rename function.
>
> Please rephrase your question and send it to bug-coreutils@gnu.org.
>
> Thanks
> Bob
>

Appreciate the email bob, will get with bug-coreutils@gnu.org.



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