[26357] in Perl-Users-Digest
Perl-Users Digest, Issue: 8530 Volume: 10
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Mon Oct 17 00:05:33 2005
Date: Sun, 16 Oct 2005 21:05:05 -0700 (PDT)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Sun, 16 Oct 2005 Volume: 10 Number: 8530
Today's topics:
Re: core dump after alarm goes off xhoster@gmail.com
Re: Hash of array access tricks. Sorry, long. <lawrence@hummer.not-here.net>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: 16 Oct 2005 22:42:53 GMT
From: xhoster@gmail.com
Subject: Re: core dump after alarm goes off
Message-Id: <20051016184253.593$8U@newsreader.com>
colonel@monmouth.com (The Pied Typer) wrote:
> I have several related memory- and output-intensive Perl programs.
> They all have a timeout option that uses the alarm function. The ALRM
> handler goes into a temporary directory, unlinks all the files, removes
> the directory, and exits.
>
> These programs very often dump core after running the handler.
What version of Perl?
perlipc:
Prior to Perl 5.7.3 it was necessary to do as little as you possibly
could in your handler; notice how all we do is set a global variable
and then raise an exception. That's because on most systems,
libraries are not re-entrant; particularly, memory allocation and
I/O routines are not. That meant that doing nearly anything in your
handler could in theory trigger a memory fault and subsequent core
dump - see "Deferred Signals" below.
Xho
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Date: 16 Oct 2005 17:29:13 -0700
From: Lawrence Statton N1GAK/XE2 <lawrence@hummer.not-here.net>
Subject: Re: Hash of array access tricks. Sorry, long.
Message-Id: <x7ek6lrnom.fsf@hummer.i-did-not-set--mail-host-address--so-shoot-me>
"s. keeling" <keeling@spots.ab.ca> writes:
> Lawrence Statton N1GAK/XE2 <lawrence@hummer.not-here.net>:
> > "s. keeling" <keeling@spots.ab.ca> writes:
> >
> > > s. keeling <keeling@spots.ab.ca>:
> > > > I've built a HoA as so:
> > > >
> > > > my %prompt = (
> > > > FIRST_NAME => [ qq(NULL), qq(NULL), qq(\tFirst name -> ),
> > > > qq(You MUST supply a first name.\n) ],
> > > > LAST_NAME => [ qq(NULL), qq(NULL), qq(\tLast name -> ),
> > > > qq(You MUST supply a last name.\n) ],
> > > >
> > > > and so on. I'd like to write to and access $prompt->{$key}[2] when
> > > > prompting a user for the name, and I'd like to stuff the reply in
> > > > $prompt{$key}[1], then compare that with $prompt->{$key}[0], which
> > > > I'll try to supply via a call to mysql. :-)
> > >
> > > I should also say for some reason it won't work if I don't declare
> > > both $prompt and %prompt, ... or should I just be "my"ing the former
> >
> > perhaps this will help you understand...
> >
> > #!/usr/bin/perl
>
> Well,it adds to the mystery.
>
> > %prompt at $prompt are different variables.... Just WISHING $prompt
> > to become a refrence to %prompt will not make it so.
>
> It seems my books disagreed, as I understood them. Now I see a
> construct I hadn't seen necessary 'til now: @{$prompt->{$key}[2]}. Thx.
>
Okay, drawing a picture
%promt = ( this => [ qw / one two three / ] ,
that => [ qw / four five six / ] );
There is *NO SUCH THING* as $prompt->{this}
There is *NO SUCH THING* as $prompt->{this}[2]
There *IS* $prompt{this}
There *IS* a value for $prompt{this}[2]
What you have had explained several times and failed to understand
$prompt{$k} is not the same as $prompt->{$k}
One is an element of a hash; the other is an element of a hashref.
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
Lawrence Statton - lawrenabae@abaluon.abaom s/aba/c/g
Computer software consists of only two components: ones and
zeros, in roughly equal proportions. All that is required is to
sort them into the correct order.
------------------------------
Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin)
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>
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End of Perl-Users Digest V10 Issue 8530
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