bash question

[Peter L. Peres]

On Tue, 5 Oct 2004, Chris F.A. Johnson wrote:

>> I have asked this before: how does one expand parameters in bash for 
>> indirection ?
>> 
>> Specifically:
>> 
>> foo=123
>> bar=foo
>> 
>> now, what do I do to get the contents of foo knowing bar. I.e.:
>> 
>> baz=?!?(bar) such that baz=123
>> 
>> (find the ?!? operator, without using the name foo explicitly). I tried 
>> various ${:=} etc expansions with no luck.
>
>   In bash:
>
> baz=${!bar}
>
>   In any Bourne-type shell (including bash):
>
> eval baz=\$$bar

Thanks a lot, that's it. Bash is an example of documentation overload 
imho. Manpage has only 8377 lines (about 140 pages when printed on A4 
paper - no I did not print it out) and I tried to go through it several 
times. Otoh what happens to ${!bar} if history expansion is turned on ? No 
problem ?

Peter
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