Re: converting array to string by quoting each element for eval

[Chris F.A. Johnson]

On Tue, 15 Nov 2011, Peng Yu wrote:

> >    In any case, combining a command and its arguments in a single
> >    string is almost always the wrong way to go about it.
>
> Please compare the two scripts and see if the second one makes more sense.
>
> /tmp$ cat not_convert_args_to_string.sh
> #!/bin/bash
>
> options="$2"
> find $1 $options
> echo find $1 $options

  More sensible would be to have each option a separate argument and
  do:

location=$1
shift
find "$location" "$@"

> /tmp$ cat convert_args_to_string.sh
> #!/bin/bash
>
> options="$2"
> cmd="find $1 $options"
> eval "$cmd"
> echo $cmd

   See above.

> /tmp$ ./not_convert_args_to_string.sh . "-type f -name '*'"
> find: `./cvcd': Permission denied
> find . -type f -name '*'

   Use 'set -x' to see exactly what your script is doing.

--
   Chris F.A. Johnson, <http://cfajohnson.com/>
   Author:
   Pro Bash Programming: Scripting the GNU/Linux Shell (2009, Apress)
   Shell Scripting Recipes: A Problem-Solution Approach (2005, Apress)