Re: [Bashburn-info] A few more issues...

[Steven W. O. <st...@sy...>]

On Tuesday, Sep 23rd 2008 at 09:50 -0000, quoth Nick Warne:

=>On Tue, 23 Sep 2008 09:46:33 -0400 (EDT)
=>"Steven W. Orr" <st...@sy...> wrote:
=>
=>> On Tuesday, Sep 23rd 2008 at 09:34 -0000, quoth Nick Warne:
=>> 
=>> =>OK, good stuff, but issue #1 still fails:
=>> =>
=>> =>--> The grep function that pulls in the (regex'ed)  fstab entries
=>> =>--> doesn't work when you go to configure devices - I don't know
=>> why. =>
=>> =>There should be a list like /dev/cdrom /mnt/cdrom etc. appear at the
=>> =>bottom when entering configuration options 0) 1) and 2)
=>> 
=>> Also fixed. Thanks :-)
=>> 
=>> 565 > svn ci
=>> Sending        trunk/BashBurn.sh
=>> Sending        trunk/menus/bbmenu.sh
=>> Transmitting file data ..
=>> Committed revision 566.
=>
=>info_cmd[ii]="${!4}"
=>
=>I don't think I would have got that in a million years (well,
=>maybe ;-)  )
=>
=>Good stuff.

It's an important idiom. It's one of the ways that bash can simulate 
something that vaguely smells like pointers.

foo=abc
bar=foo
echo "${!bar} == abc"

Before this construct was supported, we had to do it the hard way.

foo=abc
bar=foo
echo $(eval "echo \$${bar}")

One of the problems with bash is that it doesn't give us the ability to 
indirect through the name of an array variable. 

That leads to uglyosities like this in bbconfmenu. menuname is something 
like conf_menuitems or advancedmenu.

        size=$(eval "echo \"\${#$menuname[@]}\"" )
        for (( ii=0; ii<size; ii++ ))
        do
            descriptors[ii]=$(eval "echo \"\${$menuname[ii]}\"" )
        done

-- 
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