Re: [gentoo-user] Re: emerge of ksh93 erroring out.. who can interpret

[Alex Schuster]

reader@×××××××.com writes:

> So I'm interested in what I might run into.  So far it looks like it
> would be ALMOST as easy as symlinking ksh to bash in /bin.

Uh, this sounds scary :)

> The two big things I see that will cause that not to work are lots of
> calls to `print' and that bash does not understand the easy way you
> can create an array in ksh:
>   `set -A array somecmd'
> creating an array of the output of somecmd.
>
> So the print calls and array creation would cause failure in nearly
> all my scripts.
>
> Someone on comp.unix.shell pointed out I could create a
>      `print() { echo -e "$@" }'
> function in bash and add that to my old ksh scripts.  So that would
> cover the print calls in most cases but still pondering the array
> part.

I do not know about ksh, but if the former statement creates an array with 
the i'th element containing the i'th word of somecmd's output, it should 
work like this:
	array=( $( somecmd ) )

If you need the i'th line, not the i'th word, do it like this, changing the 
internal field separator to newlines only:
	oldIFS=$IFS
	IFS=$'\n'
	array=( $( somecmd ) )
	IFS=$oldIFS

If you want to keep your notation, something like this might work. If the 
first parameter of a call to set is -A, it creates the array, or else it 
calls the bash set builtin:

	set ()
	{
		if [[ $1 == -A ]]
		then
			eval "$2=( $( $3 ) )"
		else
			set "$@"
		fi
	}


> I don't have so many with array calls but enough that it would be some
> work to fix.
>
> But back to your comments. "The bugs. [...]"
>
> Can you cite some actual examples of what you are talking about, with
> enough detail so I can see what you mean?  Maybe include one or two of
> the workarounds you are tired of dealing with?

I also had trouble with some bash bugs(*), and have some workarounds in my 
scripts, in case they run with older bash versions. But as I cannot ensure 
the client systems run kash or zsh, I did not bother to learn them, and 
chose bash as my shell. It's amazing what it can do, but I guess zsh and 
ksh can do the same, or even more.

(*) One was that I once needed to escape backslashes in ${//...} notations, 
but now I must not do so any more:
	(( BASH_VERSINFO < 3 )) &&
		ospath=${1//\\\\//} ||
		ospath=${1//\\//}

The other problem was with the =~ notation and quoting of the regular 
expression not being allowed any more. Workaround is to define a variable 
(foo) with the expression: [[ "blabla" =~ $foo ]]

	Wonko
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