Re: conditional aliases are broken

[Eric Blake]

On 08/18/2011 11:38 AM, Stefano Lattarini wrote:
> Hi Eric.
>
> On Thursday 18 August 2011, Eric Blake wrote:
> > On 08/18/2011 08:44 AM, Eric Blake wrote:
> > > > how do I write a function that would print the same as
> > > > $ \ls | cat
> >
> > Useless use of cat.  This can be done with \ls -1.
> >
> > > f(){ for a in "$@"; do echo "$a"; done; }

Actually, echo "$a" is not portable - if you have any file names 
beginning with - or containing \, then the results can be corrupted.

> > Or skip the loop altogether:
> >
> > f(){ printf %s\\n "%@"; }
> I think you've made a typo here; it should have been:
>
>   f () { printf %s\\n "$@"; }

Yep, slip of one key when I typed (at least on my keyboard, % and $ are 
neighbors).

> I guess that's what you meant, right?
>
> BTW, is this behaviour truly portable to other shells and/or printf
> utilities?  POSIX seems to require it to portable, but you never
> know ...

It's portable, but not always fast (some shells lack printf(1) as a 
builtin, and end up spawning a process).  And in the case of arbitrary 
file names, printf is always better than echo, since it handles \ and 
leading - correctly.

--
Eric Blake   eblake@redhat.com    +1-801-349-2682
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