[24099] in Perl-Users-Digest
Perl-Users Digest, Issue: 6293 Volume: 10
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Tue Mar 23 06:05:53 2004
Date: Tue, 23 Mar 2004 03:05:08 -0800 (PST)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Tue, 23 Mar 2004 Volume: 10 Number: 6293
Today's topics:
Re: Attempt to free unrefferenced scalar: <Joe.Smith@inwap.com>
Re: Attempt to free unrefferenced scalar: <simon@unisolve.com.au>
Counting elements in array <nospam@nospam.com>
Re: Counting elements in array <jurgenex@hotmail.com>
Re: Counting elements in array <jurgenex@hotmail.com>
Re: Counting elements in array <nospam@nospam.com>
Re: Counting elements in array <nobull@mail.com>
Re: Counting elements in array <postmaster@castleamber.com>
Re: Counting elements in array <gnari@simnet.is>
Re: emacs cperl-mode: indentation and so on... <solo@isd.dp.ua>
Re: FIFO problem - yet another .sig rot script... <abaugher@esc.pike.il.us>
Re: FIFO problem - yet another .sig rot script... <bik.mido@tiscalinet.it>
Re: FIFO problem - yet another .sig rot script... (Anno Siegel)
Re: how to execute two commands? <Joe.Smith@inwap.com>
Re: open(filehandle... is failing <Joe.Smith@inwap.com>
Re: perl module for file downloading? <Joe.Smith@inwap.com>
Re: Perl upgraded = problem resurfacing <tadmc@augustmail.com>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@augustmail.com
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Tue, 23 Mar 2004 10:29:30 GMT
From: Joe Smith <Joe.Smith@inwap.com>
Subject: Re: Attempt to free unrefferenced scalar:
Message-Id: <ekU7c.63325$JL2.835767@attbi_s03>
Jim Canfield wrote:
> Attempt to free unrefferenced scalar: SV 0x1e20874
That's a bug. From the command line, use
perlbug -s "Attempt to free unreferenced scalar: SV 0x1e20874"
to submit a bug report. Be sure to copy-and-paste the relevant
data, as re-typing is prone to typos (like the "ff" in the
quoted line above).
-Joe
------------------------------
Date: Tue, 23 Mar 2004 14:53:45 +1100
From: Simon Taylor <simon@unisolve.com.au>
Subject: Re: Attempt to free unrefferenced scalar:
Message-Id: <c3ocft$p79$1@otis.netspace.net.au>
Hello Jim,
Jim Canfield wrote:
>>Please do not re-type warning messages.
>>
>
> Thanks, I appreciate the constructive criticism, but it gets me no closer to
> figuring out this crazy error. Can anyone at least tell me if there is a
> module or something that can output which scalar might be in question? Or
> what the address means?
>
>
Yes but Tad's point is essentially that 'the devil is in the details',
and the details are best addressed by pasting exactly what you're seeing
into your post.
I've tried to reproduce the problem here and was not able to.
How small an example of the problem can you create yourself that still
manifests the symptom?
If you're able to create a 10-30 line stand-alone example then please
post it and I'll give it a go.
If not, then the simple act of trying to reproduce the bug in a small
test case will, often in itself highlight the problem for you.
Hope to hear from you.
Simon Taylor
--
Unisolve Pty Ltd - Melbourne, Australia
------------------------------
Date: Tue, 23 Mar 2004 13:23:13 +1100
From: "meme" <nospam@nospam.com>
Subject: Counting elements in array
Message-Id: <c3o6s4$9il$1@perki.connect.com.au>
How can I count the number of different elements in an array.
ie. I would like this kind of output
(W32/Netsky.d@MM) = 17
(W32/Netsky.b@MM) = 4
Some other virus = 24
etc....
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`
#!/usr/bin/perl -w
use strict;
my $logfile = "./maillog";
my ( @logbuffer, @vir, $vir, $line);
open( LOGFILE, "<$logfile" )
|| die "Error opening local log file: $!";
@logbuffer = <LOGFILE>;
foreach my $line (@logbuffer) {
unless ( $line !~ /INFECTED/ ) {
$vir = ( split(/ /, $line ) )[7];
push @vir, $vir;
}
}
close LOGFILE;
print @vir;
OUTPUT
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32
/Netsky.d@MM),(W32/Netsky.b@MM),(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32/Net
sky.b@MM),(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32/Netsky.
d@MM),(W32/Netsky.d@MM),(W32/Netsky.c@MM),(W32/Netsky.d@MM),(W32/Netsky.d@MM
),(W32/Netsky.d@MM),(W32/Netsky.d@MM),(W32/Netsky.c@MM),(W32/Netsky.d@MM),(W
32/Netsky.d@MM),(W32/Netsky.d@MM)
------------------------------
Date: Tue, 23 Mar 2004 02:36:14 GMT
From: "Jürgen Exner" <jurgenex@hotmail.com>
Subject: Re: Counting elements in array
Message-Id: <yoN7c.460$bX5.401@nwrddc02.gnilink.net>
meme wrote:
> How can I count the number of different elements in an array.
"perldoc -f duplicate" should get you started.
Once you've implemented that just take the number of keys from the hash.
jue
------------------------------
Date: Tue, 23 Mar 2004 02:36:52 GMT
From: "Jürgen Exner" <jurgenex@hotmail.com>
Subject: Re: Counting elements in array
Message-Id: <8pN7c.467$bX5.5@nwrddc02.gnilink.net>
Jürgen Exner wrote:
> meme wrote:
>> How can I count the number of different elements in an array.
>
> "perldoc -f duplicate" should get you started.
> Once you've implemented that just take the number of keys from the
> hash.
Arrrg, make that "perldoc -q duplicate", of course
jue
------------------------------
Date: Tue, 23 Mar 2004 16:25:56 +1100
From: "meme" <nospam@nospam.com>
Subject: Re: Counting elements in array
Message-Id: <c3ohn3$frl$1@perki.connect.com.au>
"Jürgen Exner" <jurgenex@hotmail.com> wrote in message
news:8pN7c.467$bX5.5@nwrddc02.gnilink.net...
> Jürgen Exner wrote:
> > meme wrote:
> >> How can I count the number of different elements in an array.
> >
> > "perldoc -f duplicate" should get you started.
> > Once you've implemented that just take the number of keys from the
> > hash.
>
> Arrrg, make that "perldoc -q duplicate", of course
>
> jue
>
>
Kewl thanxs, this is how I ended up doing it.
#!/usr/bin/perl -w
use strict;
my $logfile = "./maillog";
my ( @logbuffer, @vir, $vir, $line, $count, @count, %saw);
open( LOGFILE, "<$logfile" )
|| die "Error opening local log file: $!";
@logbuffer = <LOGFILE>;
foreach my $line (@logbuffer) {
unless ( $line !~ /INFECTED/ ) {
$vir = ( split(/ /, $line ) )[7];
push @vir, $vir;
}
}
close LOGFILE;
undef %saw;
@count = grep(!$saw{$_}++, @vir);
foreach (keys %saw) {
print "$_ = $saw{$_}\n";}
OUTPUT
~~~~~~~~~~~~~~~~~~~~~~~~~~
(W32/Netsky.b@MM), = 2
(W32/Netsky.d@MM), = 19
(W32/Netsky.c@MM), = 2
------------------------------
Date: 23 Mar 2004 09:08:11 +0000
From: Brian McCauley <nobull@mail.com>
Subject: Re: Counting elements in array
Message-Id: <u9r7vkexs4.fsf@wcl-l.bham.ac.uk>
"meme" <nospam@nospam.com> writes:
> "Jürgen Exner" <jurgenex@hotmail.com> wrote in message
> news:8pN7c.467$bX5.5@nwrddc02.gnilink.net...
> > Jürgen Exner wrote:
> > > meme wrote:
> > >> How can I count the number of different elements in an array.
> > >
> > > "perldoc -f duplicate" should get you started.
> > > Once you've implemented that just take the number of keys from the
> > > hash.
> >
> > Arrrg, make that "perldoc -q duplicate", of course
> >
> > jue
> >
> >
>
>
> Kewl thanxs, this is how I ended up doing it.
>
> #!/usr/bin/perl -w
Unless backward compatability with pre-5.6 Perl is an issue the "use
warnings" is preferable to -w.
> use strict;
>
> my $logfile = "./maillog";
>
> my ( @logbuffer, @vir, $vir, $line, $count, @count, %saw);
You are suffering from premature declaration.
You never use (this) $line.
> open( LOGFILE, "<$logfile" )
> || die "Error opening local log file: $!";
> @logbuffer = <LOGFILE>;
This is where you should have declared @logbuffer.
> foreach my $line (@logbuffer) {
Why did you slurp at all? I don't see you ever use @logbuffer again.
Much better to process the file a line at a time.
> unless ( $line !~ /INFECTED/ ) {
Double negative?
> $vir = ( split(/ /, $line ) )[7];
$vir is never used outside this block. So this is where you should
have declared $vir.
> push @vir, $vir;
> }
> }
> close LOGFILE;
>
> undef %saw;
This is where you should have declared %saw.
> @count = grep(!$saw{$_}++, @vir);
You never use @count. The above should be a for() not a grep(). But
then again @vir is redundant, you may as well have just done
$saw{$vir}++ inside the first loop.
> foreach (keys %saw) {
> print "$_ = $saw{$_}\n";}
#!/usr/bin/perl
use strict;
use warnings;
my $logfile = "./maillog";
open( LOGFILE, '<', $logfile )
|| die "Error opening local log file: $!";
my %saw;
while ( my $line = <LOGFILE> ) {
if ( $line =~ /INFECTED/ ) {
my $vir = ( split(/ /, $line ) )[7];
!$saw{$vir}++;
}
}
close LOGFILE;
foreach (keys %saw) {
print "$_ = $saw{$_}\n";}
--
\\ ( )
. _\\__[oo
.__/ \\ /\@
. l___\\
# ll l\\
###LL LL\\
------------------------------
Date: Tue, 23 Mar 2004 03:22:08 -0600
From: John Bokma <postmaster@castleamber.com>
Subject: Re: Counting elements in array
Message-Id: <40600218$0$24339$58c7af7e@news.kabelfoon.nl>
Brian McCauley wrote:
> while ( my $line = <LOGFILE> ) {
next unless $line =~ /INFECTED/;
more readable, IMHO.
--
John personal page: http://johnbokma.com/
Freelance Perl / Java developer available - http://castleamber.com/
------------------------------
Date: Tue, 23 Mar 2004 08:18:11 -0000
From: "gnari" <gnari@simnet.is>
Subject: Re: Counting elements in array
Message-Id: <c3orps$v5h$1@news.simnet.is>
"meme" <nospam@nospam.com> wrote in message
news:c3ohn3$frl$1@perki.connect.com.au...
> "Jürgen Exner" <jurgenex@hotmail.com> wrote in message
> news:8pN7c.467$bX5.5@nwrddc02.gnilink.net...
> > Jürgen Exner wrote:
[duplicate FAQ]
>
> Kewl thanxs, this is how I ended up doing it.
assumming you want criticism:
>
> #!/usr/bin/perl -w
ok, but with new perls, the current practice is
#!/usr/bin/perl
use warnings;
>
> use strict;
>
> my $logfile = "./maillog";
>
> my ( @logbuffer, @vir, $vir, $line, $count, @count, %saw);
some of these do not seem to be used
$line is redeclared a bit later
$vir should properly be declared in its innermost
scope (the unless {})
>
> open( LOGFILE, "<$logfile" )
> || die "Error opening local log file: $!";
I prefer to use 'or' instead of '||' here, due
to the precedence difference.
> @logbuffer = <LOGFILE>;
>
> foreach my $line (@logbuffer) {
if there are many lines then it is more efficient
not to slurp the file unless the array needs to be used later
while (my $line=<LOGFILE>) {
> unless ( $line !~ /INFECTED/ ) {
> $vir = ( split(/ /, $line ) )[7];
here is the proper plave to declare $vir
my $vir = ( split(/ /, $line ) )[7];
> push @vir, $vir;
if you do not need the @vir array for anything else,
you can do away with it and do the dupl count here
$saw{$vir}++;
> }
> }
> close LOGFILE;
>
> undef %saw;
you do not need this, as you initialized it in
the my () above.
> @count = grep(!$saw{$_}++, @vir);
not needed anymore
> foreach (keys %saw) {
> print "$_ = $saw{$_}\n";}
>
gnari
------------------------------
Date: Tue, 23 Mar 2004 11:00:58 +0200
From: Serge Olkhowik <solo@isd.dp.ua>
Subject: Re: emacs cperl-mode: indentation and so on...
Message-Id: <87d674gcol.fsf@isolkhowik.isd.dp.ua>
On Mon, 22 Mar 2004 22:06:47 GMT
Cedros (Cedros) wrote:
Cedros> I'm learning perl and I want to use emacs and his cperl mode. I have
Cedros> some problems:
Cedros> - when I open a perl program, emacs run perl mode, not cperl. How
Cedros> can I do to have cperl as default?
Try
(autoload 'perl-mode "cperl-mode" "alternate mode for editing Perl programs" t)
Cedros> - also if I run cperl with M-x cperl-mode, I'm not able to have a
Cedros> decent indentation: if I press enter, emacs always return to
Cedros> first column next line. What are keys to have a decent
Cedros> indentation? (in VHDL-mode I use M-q but here it seems it
Cedros> doesn't function.
Try to press C-c C-a and it'll autoindent after you enter ";" or just press
tab key.
--
Serge Olkhowik <solo@isd.dp.ua>
ISD Configuration Management Team <cm@isd.dp.ua>
------------------------------
Date: Mon, 22 Mar 2004 21:31:30 -0600
From: Aaron Baugher <abaugher@esc.pike.il.us>
Subject: Re: FIFO problem - yet another .sig rot script...
Message-Id: <864qsg8cj1.fsf@cail.baugher.pike.il.us>
Michele Dondi <bik.mido@tiscalinet.it> writes:
> Also, it *seems* that .signature is not checked to be a regular
> file, since a symlink works too, but of course it may explicitly
> check that it is *not* a FIFO, even if I can't understand why the
> hell it should!!
I've had that problem with Apache. It refuses to read from a FIFO,
and just gives an error in the log about the object not being a
regular file or directory. Irritating. I suppose one of these days
I'll patch my copy to fix that.
> I even tried a mid-hearted attempt at using a symlink to the actual
> FIFO as the .sig file, but it fails quite as miserably...
I tried that with Apache too. Didn't help.
--
Aaron
abaugher@esc.pike.il.us
------------------------------
Date: Tue, 23 Mar 2004 07:41:28 +0100
From: Michele Dondi <bik.mido@tiscalinet.it>
Subject: Re: FIFO problem - yet another .sig rot script...
Message-Id: <dtmv505o0obaufip6b2obegf6sv6s1gumv@4ax.com>
On 22 Mar 2004 09:49:18 GMT, anno4000@lublin.zrz.tu-berlin.de (Anno
Siegel) wrote:
>I believe your error is that you recreate the fifo each time around
>the loop. That may irritate pine more than the fact it is a fifo.
Do I?!?
I thought that the main difference is that I use POSIX.pm's mkfifo()
but only unless -p...
>The following skeleton script works with my pine as intended:
[snip code]
Well, I tried it as is but fails quite as miserably as mine: it dies
silently and I get a 'Broken pipe' message on tty (from the kernel?)
BTW: I've tried it at two locations with two different distros and
possibly two different versions of pine. Out of curiosity: which is
yours?
As a side note, if the pipe is there but no process is writing to it,
in both cases pine hangs and if I start the script, then it unblocks,
but the script dies as usual...
>--
>spruch 1
Hehe!!
Michele
--
you'll see that it shouldn't be so. AND, the writting as usuall is
fantastic incompetent. To illustrate, i quote:
- Xah Lee trolling on clpmisc,
"perl bug File::Basename and Perl's nature"
------------------------------
Date: 23 Mar 2004 08:37:31 GMT
From: anno4000@lublin.zrz.tu-berlin.de (Anno Siegel)
Subject: Re: FIFO problem - yet another .sig rot script...
Message-Id: <c3ot0b$1oc$1@mamenchi.zrz.TU-Berlin.DE>
Michele Dondi <bik.mido@tiscalinet.it> wrote in comp.lang.perl.misc:
> On 22 Mar 2004 09:49:18 GMT, anno4000@lublin.zrz.tu-berlin.de (Anno
> Siegel) wrote:
>
> >I believe your error is that you recreate the fifo each time around
> >the loop. That may irritate pine more than the fact it is a fifo.
>
> Do I?!?
Sorry, no, you don't. I don't think re-creating the pipe in the
loop is going to do much good (the client is already running), but
you don't do it every time, as I thought.
> I thought that the main difference is that I use POSIX.pm's mkfifo()
> but only unless -p...
>
> >The following skeleton script works with my pine as intended:
> [snip code]
>
> Well, I tried it as is but fails quite as miserably as mine: it dies
> silently and I get a 'Broken pipe' message on tty (from the kernel?)
>
> BTW: I've tried it at two locations with two different distros and
> possibly two different versions of pine. Out of curiosity: which is
> yours?
Pine 4.04, Perl v5.8.1, Linux kernel 2.0.36
> As a side note, if the pipe is there but no process is writing to it,
> in both cases pine hangs and if I start the script, then it unblocks,
> but the script dies as usual...
I see the sig-server die with broken pipe when I start the client first
(pine or something else). When the server is already up, it works
as planned.
> >--
> >spruch 1
>
> Hehe!!
Oops. See, it works! Just hope I didn't send any official mail
like that :)
Anno
------------------------------
Date: Tue, 23 Mar 2004 09:50:17 GMT
From: Joe Smith <Joe.Smith@inwap.com>
Subject: Re: how to execute two commands?
Message-Id: <tLT7c.67577$SR1.118061@attbi_s04>
Jim roos wrote:
> How can i write the date into a specific file? date > file
First, play with this little program:
my $timestamp = localtime;
print "$timestamp\n";
The rest should be obvious.
-Joe
------------------------------
Date: Tue, 23 Mar 2004 08:40:15 GMT
From: Joe Smith <Joe.Smith@inwap.com>
Subject: Re: open(filehandle... is failing
Message-Id: <PJS7c.67356$SR1.118319@attbi_s04>
Dave Smith wrote:
> I converted to the system command and it is returning a 2 and failing.
> I'm reading the perldoc but I don't see what that would indicate. Thanks
> for all your help.
For Unix-like Operating Systems, a return code of 2 from system() indicates
a SIGINT (signalled interrupt).
linux% perl -le 'print system("sleep 3600")'
^C
2
There I typed a Control-C while perl was waiting for 'sleep 3600' to
finish, and it reported that the child process died on signal number 2.
-Joe
------------------------------
Date: Tue, 23 Mar 2004 10:26:36 GMT
From: Joe Smith <Joe.Smith@inwap.com>
Subject: Re: perl module for file downloading?
Message-Id: <whU7c.63315$JL2.836735@attbi_s03>
Stijn De Saeger wrote:
> thanks a lot... I thought the LWP module only did html processing.
LWP handles HTTP and FTP protocols; it does not do any HTML processing at all.
-Joe
------------------------------
Date: Mon, 22 Mar 2004 20:33:27 -0600
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: Perl upgraded = problem resurfacing
Message-Id: <slrnc5v8fn.ain.tadmc@magna.augustmail.com>
Grant <emailgrant123@yahoo.com> wrote:
> One more thing: The "<?xml" characters will always be at the very
> beginning of the response. Is there a better way to write:
>
> if ($response =~ /^<\?xml/ ) {
>
> knowing that?
Regexes are not the Right Tool for constant strings:
if ( index($response, '<?xml') == 0 ) {
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: Tue, 23 Mar 2004 02:22:33 -0600
From: tadmc@augustmail.com
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.5 $)
Message-Id: <U_-dnXpmtL9UbsLd4p2dnA@august.net>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
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- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
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- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.5 $)
This newsgroup, commonly called clpmisc, is a technical newsgroup
intended to be used for discussion of Perl related issues (except job
postings), whether it be comments or questions.
As you would expect, clpmisc discussions are usually very technical in
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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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You should either find out where the docs got installed on your system,
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Checking the FAQ before posting is required in Big 8 newsgroups in
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customs. Each newsgroup has specific customs and rituals. Knowing
these before you participate will help avoid embarrassing social
situations. Consider yourself to be a foreigner at first!
Search a Usenet archive
There are tens of thousands of Perl programmers. It is very likely
that your question has already been asked (and answered). See if you
can find where it has already been answered.
One such searchable archive is:
http://groups.google.com/advanced_group_search
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 <tadmc@augustmail.com> and many others on the
comp.lang.perl.misc newsgroup.
------------------------------
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 6293
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