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Re: it's safe to run a web hosting server with the unstable distributions ?



Typing away merrily, John Haggerty produced the immortal words:
> If you need source that badly or ever need it in the future just get some
> copies of everything and burn some CDs for permanent archival storage. You
> can't go wrong there.

We've now made sure that it's on a central CVS server in the UK.  Much
redundancy in the RAID, and backed up.

Somehow, someone had neglected to ensure that we had perl4 source
around.  Not all _that_ surprising - at the time it was probably taken
for granted that it was widely available.

> I think in upgrading something like perl4 you could hire say one
> programmer to do a temporary job and be on call for you. Then fix
> everything. I may be incorrect but isn't most of the core language of perl
> pretty much constant? Kind of like C/C++ or perl/delphi

It tends to be backwards compatible - new features are added, so you can
test for a minimum version number.  The move from perl4 to perl5 was hot
entirely backwards compatible, though.  As an example of the most
commonly encountered problem, in perl 4 arrays were not interpolated
into double-quoted strings.  So, given:
  @foo=(alpha, beta);
  $bar="x @foo x\n";
and the default output field separator of a single space, printing $bar
will give you:
 perl4: x @foo x
 perl5: x alpha beta x
which causes problems with, for example, email addresses (in the very
common case where double-quotes have been used unnecessarily, or it's
inside a here-document, or whatever).

There are some other smaller gotchas as well, but I don't remember them
off the top of my head as the vast majority of problems arise from the
above scenario.
-- 
HTML email - just say no --> Phil Pennock
"We've got a patent on the conquering of a country through the use of force.
 We believe in world peace through extortionate license fees."  -Bluemeat


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