Re: cp command potental problem

[Eric Blake]

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According to Bob Proulx on 6/17/2009 11:12 AM:
> If there are three program arguments then the last one must be a
> directory or it is an error.  But with only two it isn't possible to
> determine the caller's intention.

It is also possible to write shell functions or aliases so that you can
avoid some of these mistakes.  For example:

$ alias safe_copy='cp -n'
$ safe_copy file*.txt

when given only two file names from the glob will be a silent no-op rather
than overwriting the second file with contents from the first, but can
still be overridden when you mean for the overwrite to happen:

$ safe_copy -i file*.txt
cp: overwrite `file1.txt'? y

On the other hand, I just noticed that with -v, there is nothing output to
make it obvious when a copy was omitted because -n took effect; maybe it
would make sense for 'cp -vn' to be verbose about files that it refused to
copy because it would have clobbered a destination?

- --
Don't work too hard, make some time for fun as well!

Eric Blake             address@hidden
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