Re: Globbing (was Re: HAMMER update 10-Feb-2008)

[Bill Hacker <wbh@xxxxxxxxxxxxx>]

talon@lpthe.jussieu.fr wrote:
> Bill Hacker wrote:
>
> > Matthew Dillon wrote:
>
> > >     hours while csh eats up all the memory on your machine and everything
> > >     comes to a grinding stop.  It doesn't work.
> > >
> > >     People need to learn to use find, xargs, awk, etc.
> > >
> > > -Matt
> > > Matthew Dillon
> > > <dillon@backplane.com>
> >
> > All manner of insects have been found preserved in amber, so why not a
> > DragonFly?
> >
> > But they didn't *choose* to be fossilized.
>
> Bill, i agree completely with Matt.

I don't *disagree* with him myself.

It's his dime, his project, and is at least less arcane than Plan9.

> Of course you can increase the size
> of the buffer so that more globbing stuff fit in, since machines have bigger
> memories nowadays. But there will always exist side cases where one needs
> to be more sophisticated. Moreover using globbing to removes thousands
> files at one stroke exposes us to the famous 'rm a *' instead of 'rm a*'
> which certainly occurred at least once to each of us. Taking time to think
> about one wants to do, and how to do it, is better than using blind
> automatisms. And if you have carefully crafted names in your files you may
> end up removing far more than you wanted using globs, where find has
> special construct to fight against this trick ( -print0 ).

That is a reasonably accurate history lesson.  No argumant.

But it is largely irrelevant to the actual presnt-day challenge.

Managing modern fs of the size that *coders* conceive, design, 
implement, but that only real-world *users* manage to actually fill up 
*overnight*, and admins then have to deal with.  All too often.

The point is not to argue over the legacy of tools we've outgrown.
I understand how deeply embedded 'rm' and friends are in, for example, 
buildworld and siblings.

The point is to build *new* tools that *can* manage greater resources as 
we build those greater resources.

So 'rm' is no longer the right tool - or even a safely re-usable name.

But neither is some 'awk' ward script construction.
Those are even less safe or predictable - even in reasonably expert, but 
often 'too tired' hands.

So what is the point of a multi-terabyte fs if only a coder - or at 
least a 'script mavin' can *manage* them?

Are we to divide them up into tiny chunks just so the traditional tools 
can work? Hack a 'Midnight Commander' clone in userland?

I hope not.

As to 'rm /path/to/dir/*' .... or 'rm -Rf /path/to/dir/*'

Well.... if one doesn't understand what that particular 'pattern' is 
expected to match, relying on early breakage of small buffers is not a 
good enough safety anyway.

;-)

Bill