CentOS - Mar 2022 - Need fstab-decode for CentOS 8

On 3/1/22 3:46 PM, Gordon Messmer wrote:
> On 3/1/22 10:29, Gordon Messmer wrote:
>>
>> Chris Schanzle mentioned off-list that a tab character had been
replaced with spaces (I *knew* that should have been an attached file, shame on
me).? He also suggested an improvement that removes the tab character, so
here's a second try.
> 
> 
> Or not?? Last try.
> 
> 
> #!/bin/sh
> 
> declare -a cmdline
> tab=$'\t'
> eol=$'\n'
> 
> for arg in "$@"
> do
>  ? arg="${arg//\\011/$tab}"
>  ? arg="${arg//\\012/$eol}"
>  ? arg="${arg//\\040/ }"
>  ? arg="${arg//\\134/\\}"
>  ? arg="${arg//\\\\/\\}"
>  ? cmdline+=("$arg")
> done
> 
> "${cmdline[@]}"
The problem there is that the last line is going to get interpreted by a shell
before anything is executed, so you now have to escape characters that are
special to the shell within a quoted string. This is unlike the compiled
fstab-decode program that invokes the execvp() library call and avoids further
shell parsing.

-- 
Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.

On 3/1/22 15:36, Robert Nichols wrote:
>> "${cmdline[@]}"
>
> The problem there is that the last line is going to get interpreted by 
> a shell before anything is executed, so you now have to escape 
> characters that are special to the shell within a quoted string. This 
> is unlike the compiled fstab-decode program that invokes the execvp() 
> library call and avoids further shell parsing.

Does it, though?

$ bash fstab-decode.sh echo '$PATH'
$PATH
$ bash fstab-decode.sh ls '*'
ls: cannot access '*': No such file or directory