[30619] in Perl-Users-Digest
Perl-Users Digest, Issue: 1864 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Sep 19 14:09:49 2008
Date: Fri, 19 Sep 2008 11:09:07 -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 Fri, 19 Sep 2008 Volume: 11 Number: 1864
Today's topics:
=?windows-1252?B?SW4gd29yZCBmb3JtYXRpb24sIHdoYXQgaXMgIl languefang@163.com
=?windows-1252?B?UmU6IEluIHdvcmQgZm9ybWF0aW9uLCB3aGF0IG <smallpond@juno.com>
Re: Accessing an Array Stored in a File <damercer@comcast.net>
Re: Accessing an Array Stored in a File <john@castleamber.com>
Re: Easiest way to do this? <xemoth@gmail.com>
Re: Easiest way to do this? (hymie!)
Re: Easiest way to do this? <smallpond@juno.com>
Re: Easiest way to do this? <void.no.spam.com@gmail.com>
Re: eval, "adding up" words to create a variable? <adrian.popa.gh@gmail.com>
Re: IPC:Shareable <clauskick@hotmail.com>
Re: IPC:Shareable <ben@morrow.me.uk>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@seesig.invalid
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Fri, 19 Sep 2008 07:24:02 -0700 (PDT)
From: languefang@163.com
Subject: =?windows-1252?B?SW4gd29yZCBmb3JtYXRpb24sIHdoYXQgaXMgIlUtYmVuZCAiLCAiTy1yaW5nIiAmIJM=?= =?windows-1252?B?Uy10dWJllCBjYWxsZWQ/?=
Message-Id: <4af8b534-f89f-479a-9f10-a98eab0cf1ab@k36g2000pri.googlegroups.com>
In word formation, what is "U-bend ", "O-ring" & $B!H(BS-tube$B!I(B called?
Graphic words$B!)(BImage words$B!)(Biconic words$B!)(B Thank you. "X-ray" & "N-pole"
seems different, "X" and "N" are not about image. And what about
"pyramid"? It's about shape or form. But it's a little different.
------------------------------
Date: Fri, 19 Sep 2008 08:02:03 -0700 (PDT)
From: smallpond <smallpond@juno.com>
Subject: =?windows-1252?B?UmU6IEluIHdvcmQgZm9ybWF0aW9uLCB3aGF0IGlzICJVLWJlbmQgIiwgIk8tcmluZyIgJg==?= =?windows-1252?B?IJNTLXR1YmWUIGNhbGxlZD8=?=
Message-Id: <7c1b46e3-733b-4f4e-aa81-6ccc0787b25f@l43g2000hsh.googlegroups.com>
On Sep 19, 10:24 am, languef...@163.com wrote:
> In word formation, what is "U-bend ", "O-ring" & $B!H(BS-tube$B!I(B called?
> Graphic words$B!)(BImage words$B!)(Biconic words$B!)(B Thank you. "X-ray" & "N-pole"
> seems different, "X" and "N" are not about image. And what about
> "pyramid"? It's about shape or form. But it's a little different.
I think you posted to the wrong group but I would propose
"figurograph" from the Latin roots for shape and writing.
Pictograph or ideogram are the closest existing words in meaning.
Another example word would be "ell".
--S
------------------------------
Date: Fri, 19 Sep 2008 09:20:11 -0500
From: "Dan Mercer" <damercer@comcast.net>
Subject: Re: Accessing an Array Stored in a File
Message-Id: <5o2dnZ_nU4WaKE7VnZ2dnUVZ_ojinZ2d@comcast.com>
"cartercc" <cartercc@gmail.com> wrote in message
news:fcffb8e9-1051-4817-be10-48b5c0cebf86@z6g2000pre.googlegroups.com...
On Sep 18, 9:50 am, hamidre...@yahoo.com wrote:
> I want to use it in another Perl program. The BIG array cannot be
> loaded into memory since it is just too BIG.
>
> Any trick to use its copy in the file as an object and access it? It
> might be very slow but I don't care about speed. I just want to get
> over this memory problem.
>
> In otherwords, can Perl access an object stored in a file as if it
> were in memory?
>
> NOTE: I know I can load it in memory. I don't want to. I want to
> access it while it sits in the file.
In an array, individual elements are accessed sequentially according
to the subscript. Do the same thing with your file.
my $subscript = 0;
open BIGFILE, "<bigfile.dat";
while(<BIGFILE>)
{
if ($subscript eq $target) { process_element($_); }
elsif (/$match/) { process_element($_); }
$subscript++;
}
close BIGFILE;
}
CC
If you make the records fixed width you can use seek to access
them - much faster than the above method.
Dan Mercer
------------------------------
Date: 19 Sep 2008 16:30:39 GMT
From: John Bokma <john@castleamber.com>
Subject: Re: Accessing an Array Stored in a File
Message-Id: <Xns9B1E7517ABCFFcastleamber@130.133.1.4>
"Dan Mercer" <damercer@comcast.net> wrote:
> open BIGFILE, "<bigfile.dat";
my $filename = 'bigfile.dat';
open my $fh, '<', $filename
or die "Can't open '$filename' for reading: $!";
See perldoc -f open
--
John http://johnbokma.com/ - Hacking & Hiking in Mexico
Perl help in exchange for a gift:
http://johnbokma.com/perl/help-in-exchange-for-a-gift.html
------------------------------
Date: Fri, 19 Sep 2008 04:59:21 -0700 (PDT)
From: Owen <xemoth@gmail.com>
Subject: Re: Easiest way to do this?
Message-Id: <c847e8f5-4260-4b2c-8fc2-148ce2cccfd0@v16g2000prc.googlegroups.com>
On Sep 19, 1:23 pm, "void.no.spam....@gmail.com"
<void.no.spam....@gmail.com> wrote:
> I need to be able to take any dollar amount, such as 25103.34, and
> multiply it by 0.0000056. Then I need to take the result and truncate
> everything after the fifth decimal place, so if the result is
> 0.140578704, then I will have 0.14057. Then I need to round up to the
> nearest cent (ceiling function), so if I have 0.14057, then the result
> will be 0.15. What would be the easiest way to achieve this?
I am not sure I would do what you are doing. I would;
convert money amount to cents
use ceil function from POSIX to round up after multiplication
then use sprintf to bring it back to $s and cents
Owen
------------------------------
Date: Fri, 19 Sep 2008 08:15:42 -0500
From: hymie_@_lactose.homelinux.net (hymie!)
Subject: Re: Easiest way to do this?
Message-Id: <4didnU5eqapjOE7VnZ2dnUVZ_gCdnZ2d@comcast.com>
In our last episode, the evil Dr. Lacto had captured our hero,
<void.no.spam.com@gmail.com>, who said:
>I need to be able to take any dollar amount, such as 25103.34, and
>multiply it by 0.0000056.
>Then I need to take the result and truncate
>everything after the fifth decimal place, so if the result is
>0.140578704, then I will have 0.14057.
This seems like a useless step considering
> Then I need to round up to the
>nearest cent (ceiling function), so if I have 0.14057, then the result
>will be 0.15. What would be the easiest way to achieve this?
Convert everything into integers before doing any math.
Multiply
2510334 * 56 = 140578704
(note that you've shifted 9 decimal places)
Truncate (?)
int (140578704 / 10000) = 14057
(you've unshifted 4 decimal places)
Round up
int ((14057 + 999) / 1000) = 15
(you've unshifted 3 decimal places)
Convert back to dollars-and-cents
15 / 100 = 0.15
(you've unshifted 2 decimal places)
--hymie! http://lactose.homelinux.net/~hymie hymie@lactose.homelinux.net
------------------------ Without caffeine for 689 days ------------------------
------------------------------
Date: Fri, 19 Sep 2008 08:13:49 -0700 (PDT)
From: smallpond <smallpond@juno.com>
Subject: Re: Easiest way to do this?
Message-Id: <a6b8ae04-a1e4-42ae-b110-20d1b7439c4e@c65g2000hsa.googlegroups.com>
On Sep 19, 9:15 am, hymie_@_lactose.homelinux.net (hymie!) wrote:
> In our last episode, the evil Dr. Lacto had captured our hero,
> <void.no.spam....@gmail.com>, who said:
>
> >I need to be able to take any dollar amount, such as 25103.34, and
> >multiply it by 0.0000056.
> >Then I need to take the result and truncate
> >everything after the fifth decimal place, so if the result is
> >0.140578704, then I will have 0.14057.
>
> This seems like a useless step considering
>
> > Then I need to round up to the
> >nearest cent (ceiling function), so if I have 0.14057, then the result
> >will be 0.15. What would be the easiest way to achieve this?
>
> Convert everything into integers before doing any math.
>
> Multiply
> 2510334 * 56 = 140578704
> (note that you've shifted 9 decimal places)
>
> Truncate (?)
> int (140578704 / 10000) = 14057
> (you've unshifted 4 decimal places)
>
> Round up
> int ((14057 + 999) / 1000) = 15
> (you've unshifted 3 decimal places)
>
> Convert back to dollars-and-cents
> 15 / 100 = 0.15
> (you've unshifted 2 decimal places)
>
> --hymie! http://lactose.homelinux.net/~hymie hy...@lactose.homelinux.net
> ------------------------ Without caffeine for 689 days ------------------------
As pointed out, monetary calculation is best done as
all integer arithmetic. You can save a step in the
above procedure by only truncating once:
multiply
2510334 * 56 = 140578704
round
int ((140578704 + 9990000) / 10000000) = 15
--S
------------------------------
Date: Fri, 19 Sep 2008 10:13:29 -0700 (PDT)
From: "void.no.spam.com@gmail.com" <void.no.spam.com@gmail.com>
Subject: Re: Easiest way to do this?
Message-Id: <1cf5a698-dede-4a5c-9194-6182bad9cfce@x41g2000hsb.googlegroups.com>
On Sep 19, 9:15=A0am, hymie_@_lactose.homelinux.net (hymie!) wrote:
> In our last episode, the evil Dr. Lacto had captured our hero,
> =A0 <void.no.spam....@gmail.com>, who said:
>
> >I need to be able to take any dollar amount, such as 25103.34, and
> >multiply it by 0.0000056. =A0
> >Then I need to take the result and truncate
> >everything after the fifth decimal place, so if the result is
> >0.140578704, then I will have 0.14057.
>
> This seems like a useless step considering
Thanks for the answer. That step actually isn't useless, because if
the multiplication results in something like 0.140000001, and then you
don't truncate, the final result will be 0.15 when it should be 0.14.
> > =A0Then I need to round up to the
> >nearest cent (ceiling function), so if I have 0.14057, then the result
> >will be 0.15. =A0What would be the easiest way to achieve this?
>
> Convert everything into integers before doing any math.
>
> Multiply
> 2510334 * 56 =3D 140578704
> (note that you've shifted 9 decimal places)
>
> Truncate (?)
> int (140578704 / 10000) =3D =A014057
> (you've unshifted 4 decimal places)
>
> Round up
> int ((14057 + 999) / 1000) =3D 15
> (you've unshifted 3 decimal places)
>
> Convert back to dollars-and-cents
> 15 / 100 =3D 0.15
> (you've unshifted 2 decimal places)
>
> --hymie! =A0 =A0http://lactose.homelinux.net/~hymie=A0 =A0hy...@lactose.h=
omelinux.net
> ------------------------ Without caffeine for 689 days ------------------=
------
------------------------------
Date: Fri, 19 Sep 2008 05:33:27 -0700 (PDT)
From: mad_ady <adrian.popa.gh@gmail.com>
Subject: Re: eval, "adding up" words to create a variable?
Message-Id: <661babca-02e0-458a-8367-cac2ee8c7b2a@w7g2000hsa.googlegroups.com>
Here is why $dynamicVariableName is a bad idea; it will convince you
to switch to hashes:
http://perl.plover.com/varvarname.html
The short reason, quoted from the text:
The real problem is that if your string contains something unexpected,
it will sabotage a totally unrelated part of the program, and then you
will have one hell of a time figuring out the bug.
Cheers.
On Sep 18, 10:17=A0pm, Joost Diepenmaat <jo...@zeekat.nl> wrote:
> RedGrittyBrick <RedGrittyBr...@spamweary.invalid> writes:
> > Tomasz Chmielewski wrote:
> >> Joost Diepenmaat schrieb:
> >>> also: IMHO it's bad style to use the &foo() construct to call
> >>> functions. foo() is a little shorted and has less potential problems.
>
> >> Besides being "bad style", what potential problems can it make?
> >> (code readability? something else?)
>
> > See perldoc perlsub. It circumvents prototypes and causes current @_
> > to be visible to the called subroutine. In 99% of cases you don't want
> > this.
>
> Exactly, but note that passing on @_ only happens if you don't specify
> parentheses and no arguments, like this:
>
> sub mything {
> =A0 my ($arg) =3D @_;
> =A0 &something_else; =A0# this passes on @_ to something_else
>
> }
> > Using the &sub call notation was common in Perl 4 days but IIRC that
> > was superseded back in 1993, more than fifteen years ago.
>
> > Presumably you are learning Perl from something that is 15 years out
> > of date.
>
> I would think so too.
>
> --
> Joost Diepenmaat | blog:http://joost.zeekat.nl/| work:http://zeekat.nl/
------------------------------
Date: Fri, 19 Sep 2008 08:29:33 -0700 (PDT)
From: Snorik <clauskick@hotmail.com>
Subject: Re: IPC:Shareable
Message-Id: <c9852a84-8652-43b3-b362-5777d87eb1cb@k37g2000hsf.googlegroups.com>
On Sep 18, 5:18=A0pm, Ben Morrow <b...@morrow.me.uk> wrote:
> Quoth Snorik <clausk...@hotmail.com>:
>
>
>
> > Hello everyone,
>
> > I am trying to speed up a few perl scripts by forking them.
> > Unfortunately, I need to pass back to the parent.
> > I am using named pipes at other places, but this time, I wanted to use
> > shared memory (this being on *nix).
>
> > The first case is basically traversing a HUGE directory tree, looking
> > for certain files and returning them.
>
> > The idea is to fork finds from a specific point of the directory tree,
> > gather all the files in an array for each child process and then store
> > that array as reference as value of the hash.
>
> > For this, I have done:
>
> > sub get_fbas_for_rg
> > =A0 {
> > =A0 =A0 =A0 =A0 =A0my $rg =3D shift;
> > =A0 =A0 =A0 =A0 =A0 my @children;
> > =A0 =A0 =A0 =A0 =A0 use IPC::Shareable;
> > =A0 =A0 =A0 =A0 =A0 use Data::Dumper;
>
> It's best not to 'use' modules inside a sub (except for lowercase
> pragmata which have lexical effect). It gives the false impression that
> the exporter subs are only available in that sub.
Ok, that is a useful remark, I will keep that in mind.
> > =A0 =A0 =A0 =A0 =A0use constant MYGLUE =3D> 'Test';
> > =A0 =A0 =A0 =A0 =A0 my %fba_hash;
> > =A0 =A0 =A0 =A0my $handle =3D tie (%fba_hash, IPC::Shareable, MYGLUE, {=
create =3D>
> > 1, mode =3D> 0666}) or die "cannot tie to shared memory: $! \n";
>
> > =A0 =A0 =A0my @ggs =3D qx (ls /default/main/www/$rg | grep -v STAGING |=
grep -
> > v WORKAREA | grep -v EDITION);
>
> =A0 =A0 use File::Slurp qw/read_dir/;
*snip useage of File::Slurp*
Thanks for pointing that out, that module really helps working a lot!
I never knew that existed.
>
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 my @fbas =3D (qx (/=
usr/bin/find /default/main/
> > www/$rg/$gg/WORKAREA/workarea/$gg_fba -type f ));
>
> I would use File::Find::Rule for this.
>
> =A0 =A0 my @fbas =3D File::Find::Rule->file
> =A0 =A0 =A0 =A0 ->in("/default/main/www/$rg/$gg/WORKAREA/workarea/$gg_fba=
");
Again, thanks for pointing that out - This is so much more elegant
than the normal File::Find way.
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 $handle->shlock();
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 push (@{$fba_hash{$gg}}=
, @fbas);
>
> You cannot assign a ref to an IPC::Shareable tied hash. The other
> process has no way of following that ref: it refers to data structures
> that aren't in shared memory. I would suggest using Storable:
OK, so if I may rephrase in order to check whether I have actually
understood:
All that can be tied in that hash is the scalar of the array (its
size), I cannot use it to follow a ref to the actual array.
> =A0 =A0 use Storable qw/freeze/;
>
> =A0 =A0 $fba_hash{$gg} =3D freeze \@fbas;
>
> and then retrieve it with
>
> =A0 =A0 use Storable qw/thaw/;
>
> =A0 =A0 my @fbas =3D @{ thaw $fba_hash{$gg} };
I have a question concerning this (I just had a look at the Storable
documentation, but this does not really clear things up):
So Storable persists (and of course serializes) any datastructure;that
means I can store the hash to disk (or memory, hopefully memory?).
How can I retrieve this in the calling script, as this sub is going to
live in a module itself? I must admit, this is my first attempt at IPC
myself.
I would be very grateful for an answer.
Snorik
------------------------------
Date: Fri, 19 Sep 2008 17:21:05 +0100
From: Ben Morrow <ben@morrow.me.uk>
Subject: Re: IPC:Shareable
Message-Id: <h40dq5-tc2.ln1@osiris.mauzo.dyndns.org>
Quoth Snorik <clauskick@hotmail.com>:
> On Sep 18, 5:18 pm, Ben Morrow <b...@morrow.me.uk> wrote:
> >
> > You cannot assign a ref to an IPC::Shareable tied hash. The other
> > process has no way of following that ref: it refers to data structures
> > that aren't in shared memory. I would suggest using Storable:
>
> OK, so if I may rephrase in order to check whether I have actually
> understood:
> All that can be tied in that hash is the scalar of the array (its
> size), I cannot use it to follow a ref to the actual array.
Yes. I don't entirely understand why the value stored was
scalar(@array): I would have expected it to be the stringification of
the ref. I guess it's to do with how IPC::Shareable interprets its
arguments.
>
> > use Storable qw/freeze/;
> >
> > $fba_hash{$gg} = freeze \@fbas;
> >
> > and then retrieve it with
> >
> > use Storable qw/thaw/;
> >
> > my @fbas = @{ thaw $fba_hash{$gg} };
>
> I have a question concerning this (I just had a look at the Storable
> documentation, but this does not really clear things up):
>
> So Storable persists (and of course serializes) any datastructure;that
> means I can store the hash to disk (or memory, hopefully memory?).
Yes. You use store/retrieve to save to and load from disk; you use
freeze/thaw to save to and load from memory.
> How can I retrieve this in the calling script, as this sub is going to
> live in a module itself? I must admit, this is my first attempt at IPC
> myself.
If you store it with 'freeze', you get it out again with 'thaw'.
Ben
--
I touch the fire and it freezes me, [ben@morrow.me.uk]
I look into it and it's black.
Why can't I feel? My skin should crack and peel---
I want the fire back... BtVS, 'Once More With Feeling'
------------------------------
Date: Fri, 19 Sep 2008 07:16:56 GMT
From: tadmc@seesig.invalid
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
Message-Id: <IlIAk.978$yr3.504@nlpi068.nbdc.sbc.com>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
- Do not provide too much information
- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
- Beware of saying "doesn't work"
- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
This newsgroup, commonly called clpmisc, is a technical newsgroup
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describes how to get answers from technical people in general.
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Must
This section describes things that you *must* do before posting to
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The perl distribution includes documentation that is copied to your hard
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You should either find out where the docs got installed on your system,
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Check the other standard Perl docs (*.pod)
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It is *not* required, or even expected, that you actually *read* all of
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Try doing a word-search in the standard docs for some words/phrases
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Lurk for a while before posting
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If You Like
This section describes things that you *can* do before posting to
clpmisc.
Check Other Resources
You may want to check in books or on web sites to see if you can
find the answer to your question.
But you need to consider the source of such information: there are a
lot of very poor Perl books and web sites, and several good ones
too, of course.
Posting to comp.lang.perl.misc
There can be 200 messages in clpmisc in a single day. Nobody is going to
read every article. They must decide somehow which articles they are
going to read, and which they will skip.
Your post is in competition with 199 other posts. You need to "win"
before a person who can help you will even read your question.
These sections describe how you can help keep your article from being
one of the "skipped" ones.
Is there a better place to ask your question?
Question should be about Perl, not about the application area
It can be difficult to separate out where your problem really is,
but you should make a conscious effort to post to the most
applicable newsgroup. That is, after all, where you are the most
likely to find the people who know how to answer your question.
Being able to "partition" a problem is an essential skill for
effectively troubleshooting programming problems. If you don't get
that right, you end up looking for answers in the wrong places.
It should be understood that you may not know that the root of your
problem is not Perl-related (the two most frequent ones are CGI and
Operating System related), so off-topic postings will happen from
time to time. Be gracious when someone helps you find a better place
to ask your question by pointing you to a more applicable newsgroup.
How to participate (post) in the clpmisc community
Carefully choose the contents of your Subject header
You have 40 precious characters of Subject to win out and be one of
the posts that gets read. Don't waste them. Take care while
composing them, they are the key that opens the door to getting an
answer.
Spend them indicating what aspect of Perl others will find if they
should decide to read your article.
Do not spend them indicating "experience level" (guru, newbie...).
Do not spend them pleading (please read, urgent, help!...).
Do not spend them on non-Subjects (Perl question, one-word
Subject...)
For more information on choosing a Subject see "Choosing Good
Subject Lines":
http://www.cpan.org/authors/id/D/DM/DMR/subjects.post
Part of the beauty of newsgroup dynamics, is that you can contribute
to the community with your very first post! If your choice of
Subject leads a fellow Perler to find the thread you are starting,
then even asking a question helps us all.
Use an effective followup style
When composing a followup, quote only enough text to establish the
context for the comments that you will add. Always indicate who
wrote the quoted material. Never quote an entire article. Never
quote a .signature (unless that is what you are commenting on).
Intersperse your comments *following* each section of quoted text to
which they relate. Unappreciated followup styles are referred to as
"top-posting", "Jeopardy" (because the answer comes before the
question), or "TOFU" (Text Over, Fullquote Under).
Reversing the chronology of the dialog makes it much harder to
understand (some folks won't even read it if written in that style).
For more information on quoting style, see:
http://web.presby.edu/~nnqadmin/nnq/nquote.html
Speak Perl rather than English, when possible
Perl is much more precise than natural language. Saying it in Perl
instead will avoid misunderstanding your question or problem.
Do not say: I have variable with "foo\tbar" in it.
Instead say: I have $var = "foo\tbar", or I have $var = 'foo\tbar',
or I have $var = <DATA> (and show the data line).
Ask perl to help you
You can ask perl itself to help you find common programming mistakes
by doing two things: enable warnings (perldoc warnings) and enable
"strict"ures (perldoc strict).
You should not bother the hundreds/thousands of readers of the
newsgroup without first seeing if a machine can help you find your
problem. It is demeaning to be asked to do the work of a machine. It
will annoy the readers of your article.
You can look up any of the messages that perl might issue to find
out what the message means and how to resolve the potential mistake
(perldoc perldiag). If you would like perl to look them up for you,
you can put "use diagnostics;" near the top of your program.
Do not re-type Perl code
Use copy/paste or your editor's "import" function rather than
attempting to type in your code. If you make a typo you will get
followups about your typos instead of about the question you are
trying to get answered.
Provide enough information
If you do the things in this item, you will have an Extremely Good
chance of getting people to try and help you with your problem!
These features are a really big bonus toward your question winning
out over all of the other posts that you are competing with.
First make a short (less than 20-30 lines) and *complete* program
that illustrates the problem you are having. People should be able
to run your program by copy/pasting the code from your article. (You
will find that doing this step very often reveals your problem
directly. Leading to an answer much more quickly and reliably than
posting to Usenet.)
Describe *precisely* the input to your program. Also provide example
input data for your program. If you need to show file input, use the
__DATA__ token (perldata.pod) to provide the file contents inside of
your Perl program.
Show the output (including the verbatim text of any messages) of
your program.
Describe how you want the output to be different from what you are
getting.
If you have no idea at all of how to code up your situation, be sure
to at least describe the 2 things that you *do* know: input and
desired output.
Do not provide too much information
Do not just post your entire program for debugging. Most especially
do not post someone *else's* entire program.
Do not post binaries, HTML, or MIME
clpmisc is a text only newsgroup. If you have images or binaries
that explain your question, put them in a publically accessible
place (like a Web server) and provide a pointer to that location. If
you include code, cut and paste it directly in the message body.
Don't attach anything to the message. Don't post vcards or HTML.
Many people (and even some Usenet servers) will automatically filter
out such messages. Many people will not be able to easily read your
post. Plain text is something everyone can read.
Social faux pas to avoid
The first two below are symptoms of lots of FAQ asking here in clpmisc.
It happens so often that folks will assume that it is happening yet
again. If you have looked but not found, or found but didn't understand
the docs, say so in your article.
Asking a Frequently Asked Question
It should be understood that you may have missed the applicable FAQ
when you checked, which is not a big deal. But if the Frequently
Asked Question is worded similar to your question, folks will assume
that you did not look at all. Don't become indignant at pointers to
the FAQ, particularly if it solves your problem.
Asking a question easily answered by a cursory doc search
If folks think you have not even tried the obvious step of reading
the docs applicable to your problem, they are likely to become
annoyed.
If you are flamed for not checking when you *did* check, then just
shrug it off (and take the answer that you got).
Asking for emailed answers
Emailed answers benefit one person. Posted answers benefit the
entire community. If folks can take the time to answer your
question, then you can take the time to go get the answer in the
same place where you asked the question.
It is OK to ask for a *copy* of the answer to be emailed, but many
will ignore such requests anyway. If you munge your address, you
should never expect (or ask) to get email in response to a Usenet
post.
Ask the question here, get the answer here (maybe).
Beware of saying "doesn't work"
This is a "red flag" phrase. If you find yourself writing that,
pause and see if you can't describe what is not working without
saying "doesn't work". That is, describe how it is not what you
want.
Sending a "stealth" Cc copy
A "stealth Cc" is when you both email and post a reply without
indicating *in the body* that you are doing so.
Be extra cautious when you get upset
Count to ten before composing a followup when you are upset
This is recommended in all Usenet newsgroups. Here in clpmisc, most
flaming sub-threads are not about any feature of Perl at all! They
are most often for what was seen as a breach of netiquette. If you
have lurked for a bit, then you will know what is expected and won't
make such posts in the first place.
But if you get upset, wait a while before writing your followup. I
recommend waiting at least 30 minutes.
Count to ten after composing and before posting when you are upset
After you have written your followup, wait *another* 30 minutes
before committing yourself by posting it. You cannot take it back
once it has been said.
AUTHOR
Tad McClellan and many others on the comp.lang.perl.misc newsgroup.
--
Tad McClellan
email: perl -le "print scalar reverse qq/moc.noitatibaher\100cmdat/"
------------------------------
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 V11 Issue 1864
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