Re: Should this be this way?

[Roman Rakus]

On 02/26/2013 02:03 AM, Linda Walsh wrote:
> My login shell is /bin/bash (i.e. not /bin/sh); SHELL=/bin/bash as well.
> Typing 'which bash' gives /bin/bash, and whence bash: bash is /bin/bash.
which is not always correct. Use type builtin.
> I had the foll0wing script which acts differently based on
> whether or not it has a #!/bin/bash at the top: (i.e., as it is
> displayed below, it fails; one need remove the [] from the first
> line for it to work.
> ================
> #[!/bin/bash]
I think the line above will produce unspecified behavior.
> while read fn;do
>    base=${fn%.*}
>    if [[ -e $base ]]; then
>      if [[ $base -ot $fn ]]; then echo "compressed version ($fn) seems newer"
>      elif [[ $base -nt $fn ]]; then echo "uncompressed version ($base)
> seem newer"
>      else echo "both versions ($base) are same age"
>      fi
>    else
>      echo "No uncompressed version of $base exists"
>    fi
> done < <(find . -type f -name \*.[0-9].\*[zZ]\* )
> -------------
> The error:
> ./manscan.sh: line 12: syntax error near unexpected token `<'
> ./manscan.sh: line 12: `done < <(find . -type f -name \*.[0-9].\*[zZ]\* )'
>
> Why would this script behave differently if the first line
> exists or not?  (Putting the !shell in square brackets,
> made it a comment, not an interpreter spec, thus the same
> effect as if it wasn't there ('cept the line number of the error is 1
> less if you don't have the line! ;-)).
>
> So...is this correct behavior for some[inane POSIX] reason?
> Seems a bit odd to me.
Is kernel or bash processing the shebang?

RR
>