general bash oddities and discussion (was Re: Syntax Question...)

[Linda Walsh]

` Greg Wooledge wrote:
> >    Now that one is suprising, as it's supposed to take the output of
> > the ... hmmm.....yup!...  that's exactly what it does.
> > takes the work and executes it and returns the results on stdin as
> > a single quoted blob of output:
> >
> >    >  read a <<< *.txt
> >    >  echo $a
> >    apc_contact.txt .chklog.txt driver_filename.txt FFcookies.txt
> >    qb2.txt rcs_kywds-exmpls.txt return_rma.txt Soundtrack-II.txt
> >    Soundtrack-I.txt winsize.txt
> >     
>
> No, you've tripped yourself by failing to quote $a in the echo command.
> "a" contains *.txt and your unquoted $a is being expanded (parameter
> expansion and then pathname expansion) with the resulting filenames
> being passed to echo.
>   
-
> "USE MORE QUOTES!"
>
>   
> > But this is weird:
> >
> >    { read a b c  } <<<*.txt  <<<*.dat  <<<*.log
> >    echo $a,  $b,  $c
> >    .bzr.log h.log q.log texput.log
> >     
>
> You're not even using valid syntax.  { read a b c; } is what you have
> to use, for a one-liner command group.  And the commas in your echo
> command are mysteriously absent in your output.
>   
--
   You're right...

I went back looking through my screen history...the above was
not cut/pasted from the right places: --- you can see what you are 
talking about
where I did this, -- (i.e the *.txt is expanded at echo time)...   BUT 
the manpage SAYS
it does pn expansion!....(at least it says that in 4.1, dunnow about 4.2).

But the actually lines...

   >  { read a b c; } <<<*.txt <<<*.dat <<<*.log
   >  echo $a
   .bzr.log h.log q.log texput.log
   >  echo $a, $b, $c
   *.log, ,

-- so you're right about the quote expansion -- ...it was in front of my
face and I looked at the wrong line!  *duh!*

Hey, I *know* I'm not perfect...that's
why I try to use so many redundant checks...because everything that can
go wrong, eventually will.   I try to write my code to protect itself 
from me, or
protect itself from other code I write....because I know I will forget 
spellings
or some call convention or something, and the program needs to tell me 
how to
fixit, as it may have been so long-ago-written, that I might not 
remember 'off hand',
so I usually try to give some indication of what died and where to look 
to fix it...

hey, I'm having to answer emails from multiple people and do catchup
(my email was 'waylaid' for about 24 hours (on my server), as my server
no longer knew who I was due to samba problems and it not resolving my
UID/name correctly for a while...