add an mv protection ?

add an mv protection ?

[Marc Chantreux]

hi all,


imagine this case :

% echo *
a.pl b.pl
% mkdir old
% mv *pl

Here, i forget the target ( old ). The result is :

mv a.pl b.pl

i've lost the b.pl content!

is there a way to hook this case and ask a confirmation ?

thanks and regards
mc

Re: add an mv protection ?

[Frank Terbeck]

Marc Chantreux <marc.chantreux@ulpmm.u-strasbg.fr>:
> % echo *
> a.pl b.pl
> % mkdir old
> % mv *pl
> 
> Here, i forget the target ( old ). The result is :
> mv a.pl b.pl
> i've lost the b.pl content!
> is there a way to hook this case and ask a confirmation ?

Hi Marc,

% man mv
[snip]
       -i, --interactive
              prompt before overwrite
[snap]

I don't know, if it's possible to check if an overwrite is intended or
not. So, if you really need it, I'd use "alias mv='mv -i'".

Regards, Frank

Re: add an mv protection ?

[Peter Stephenson]

Marc Chantreux wrote:
> % echo *
> a.pl b.pl
> % mkdir old
> % mv *pl
> 
> Here, i forget the target ( old ). The result is :
> 
> mv a.pl b.pl
> 
> i've lost the b.pl content!
> 
> is there a way to hook this case and ask a confirmation ?

Well, you can use a wrapper function:

mv() {
    if (( $# == 1 )); then
        print "mv: only one argument, did you mean that?"
        return 1
    fi
    local -a args
    args=(${~*})
    print command mv $args
}
# careful to do this after the above or you create a function "noglob"
alias mv='noglob mv'

but this isn't quite good enough, since it doesn't handle options,
for example "mv -f *.pl" or "mv -i *.pl".  An alternative approach would
be to check whether the final argument had wildcards in it, replacing
the "if" with:

   if [[ $argv[-1] = *["*?[]()#"]* ]]; then
        print "mv: last argument contains wildcards, aborted"
	return 1
   fi

but that's still not good enough if the destination might have quoted
wildcards in it.  I suppose you could use:

    local -a lastarg
    lastarg=(${~argv[-1]})
    if (( ${#lastarg} > 1 )); then
        print "mv: last argument generates multiple files, aborted"
        return 1
    fi

although that might still be imperfect.

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070


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Re: add an mv protection ?

[Patrick Börjesson]

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On 2006-05-03 11:40, Marc Chantreux uttered these thoughts:
> imagine this case :
> 
> % echo *
> a.pl b.pl
> % mkdir old
> % mv *pl
> 
> Here, i forget the target ( old ). The result is :
> 
> mv a.pl b.pl
> 
> i've lost the b.pl content!
> 
> is there a way to hook this case and ask a confirmation ?

from "man mv":
  -i     Prompt for confirmation when destination exists.  (In case  both
         -f and -i are given, the last one given takes effect.)

Regards,
 Patrick Börjesson

-- 
()  The ASCII Ribbon Campaign - against HTML Email
/\  and proprietary formats.

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Re: add an mv protection ?

[Marc Chantreux]

Thanks for your answers, I have more that i expected to write my own stuff.

thanks and regards !

mc