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Re: transports directory

[ On Mon, July 17, 1995 at 13:04:32 (-0700), Tom Samplonius wrote: ]
> Subject: Re: transports directory
>   It is easy to write scripts that work in both perl4 and perl5.  I have 
> scripts that depend on this.

Though this has no bearing on the discussion of including perl as an
extension language for Zmailer, it is an issue that must be considered
by a programmer wishing to write a portable perl script.

>   Remeber, we are talking about Zmailer.  Zmailer only works on Unix 
> systems at the present.  Who cares whether NT perl or Unix perl work 
> differently?  

Again this is more important for general perl-script portability than it
is for something which might be included as a part of Zmailer, but there
is this issue of just what system interfaces are available through the
perl interpreter.  Not all UNIX systems have the same, or compatible,
system interfaces.

Just a silly stupid example that doesn't even mention system services,
but rather only inter-application compatabilty:  Suppose you build the
Zmailer interpreter with sdbm (we want Zmailer to be portable), but
someone else installs perl with the gdbm library.  Suddenly perl scripts
external to Zmailer won't be able to operate with Zmailer db's.  Now
yes, this is silly and easy to fix, but it illustrates what I believe to
be a fundamental problem with perl:  The primitives available in the perl
interpreter are too tightly wired to the language, and there's no
standard definition of the language separate from the primitives.

Not so long ago I was involved in an effort of writing a medium-large,
portable, perl application that didn't even use most of the system
interface primitives.  It was no easier to keep it portable than it
would have been for a C program of similar functionality -- i.e. we had
to pay close and constant attention to the potential problems, but
unlike in a C program, they were rather hard to isolate into separate
modules.  Now some of these issues may have disappeared with perl-5....

							Greg A. Woods

+1 416 443-1734			VE3TCP			robohack!woods
Planix, Inc. <woods@planix.com>; Secrets of the Weird <woods@weird.com>