[19821] in Perl-Users-Digest
Perl-Users Digest, Issue: 2016 Volume: 10
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Oct 26 09:10:48 2001
Date: Fri, 26 Oct 2001 06:10:14 -0700 (PDT)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Message-Id: <1004101814-v10-i2016@ruby.oce.orst.edu>
Content-Type: text
Perl-Users Digest Fri, 26 Oct 2001 Volume: 10 Number: 2016
Today's topics:
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@augustmail.com
Re: Printing Images in a Web browser <goldbb2@earthlink.net>
problem of connection to a server FTP <clelan@tf1.fr>
Re: Regex to swap HTML tags <jimbo@soundimages.co.uk>
Re: Regex to swap HTML tags <bkrusch@fakeemail.com>
Security- Upload scripts <spamfree@sorted2000.net>
Splitting text <news@scottbell.org>
Re: Splitting text <bernard.el-hagin@lido-tech.net>
Re: Splitting text <peb@bms.umist.ac.uk>
Re: Splitting text <jurgenex@hotmail.com>
Re: Stripping Duplicates From Arrays <johni@pa.press.net>
Re: Stripping Duplicates From Arrays <mmanso@yahoo.com>
Re: Stripping Duplicates From Arrays <goldbb2@earthlink.net>
Subroutines <jvallanc@hgmp.mrc.ac.uk>
Re: Subroutines <bernard.el-hagin@lido-tech.net>
Re: Subroutines (Rafael Garcia-Suarez)
Tracing ["non-interactive debugging"] like in REXX? <edgue@web.de>
Re: Tracing ["non-interactive debugging"] like in REXX? <bernard.el-hagin@lido-tech.net>
Re: Tracing ["non-interactive debugging"] like in REXX? <edgue@web.de>
Re: Tracing ["non-interactive debugging"] like in REXX? <edgue@web.de>
Re: VVP:making a string=string. <goldbb2@earthlink.net>
Re: Win32 Perl book/software suggestions? <johni@pa.press.net>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Fri, 26 Oct 2001 12:02:31 GMT
From: tadmc@augustmail.com
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.2 $)
Message-Id: <rhcC7.32268$W87.1594158@bin4.nnrp.aus1.giganews.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: 1.2 $)
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
nature and there are conventions for conduct in technical newsgroups
going somewhat beyond those in non-technical newsgroups.
This article describes things that you should, and should not, do to
increase your chances of getting an answer to your Perl question. It is
available in POD, HTML and plain text formats at:
http://mail.augustmail.com/~tadmc/clpmisc.shtml
For more information about netiquette in general, see the "Netiquette
Guidelines" at:
http://andrew2.andrew.cmu.edu/rfc/rfc1855.html
A note to newsgroup "regulars":
Please do not use the existence of these guidelines as a
"license to flame" or other meanness. It is possible that
a poster is not aware of the things discussed here. Let's
give them the benefit of the doubt, and just help them learn
how to post, rather than assume that they do know and are
being the "bad kind" of Lazy.
A note about technical terms used here:
In this document, we use words like "must" and "should" in the
very precise sense that they're used in technical conversation
(such as you're likely to encounter in this newsgroup). When
we say that you *must* do something, we mean that if you don't
do that something, then it's very unlikely that you're going to
get much benefit from using this group. We're not trying to boss
you around; we're just trying to convey the point without using
a lot of words.
Do *NOT* send email to the maintainer of these guidelines. It will be
discarded unread. The guidelines belong to the newsgroup so all
discussion should appear in the newsgroup. I am just the secretary that
writes down the consensus of the group.
Before posting to comp.lang.perl.misc
Must
This section describes things that you *must* do before posting to
clpmisc, in order to maximize your chances of getting meaningful replies
to your inquiry and to avoid getting flamed for being lazy and trying to
have others do your work.
The perl distribution includes documentation that is copied to your hard
drive when you install perl. Also installed is a program for looking
things up in that (and other) documentation named 'perldoc'.
You should either find out where the docs got installed on your system,
or use perldoc to find them for you. Type "perldoc perldoc" to learn how
to use perldoc itself. Type "perldoc perl" to start reading Perl's
standard documentation.
Check the Perl Frequently Asked Questions (FAQ)
Checking the FAQ before posting is required in Big 8 newsgroups in
general, there is nothing clpmisc-specific about this requirement.
You are expected to do this in nearly all newsgroups.
You can use the "-q" switch with perldoc to do a word search of the
questions in the Perl FAQs.
Check the other standard Perl docs (*.pod)
The perl distribution comes with much more documentation than is
available for most other newsgroups, so in clpmisc you should also
see if you can find an answer in the other (non-FAQ) standard docs
before posting.
It is *not* required, or even expected, that you actually *read* all of
Perl's standard docs, only that you spend a few minutes searching them
before posting.
Try doing a word-search in the standard docs for some words/phrases
taken from your problem statement or from your very carefully worded
"Subject:" header.
Really Really Should
This section describes things that you *really should* do before posting
to clpmisc.
Lurk for a while before posting
This is very important and is expected regardless of what newsgroup
you are visiting. Lurking means to simply monitor a newsgroup for a
period of time until you become very familiar with local customs.
Think of a newsgroup as foreign culture. Each newsgroup has its own
specific customs and rituals. Get to know those customs and rituals
well before you participate. This will help you to 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.perl.com/CPAN-local/authors/Dean_Roehrich/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* the sections of quoted text
that your comments apply to. Failure to do this is called "Jeopardy"
posting because the answer comes before the question.
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://www.geocities.com/nnqweb/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: Fri, 26 Oct 2001 07:48:17 -0400
From: Benjamin Goldberg <goldbb2@earthlink.net>
Subject: Re: Printing Images in a Web browser
Message-Id: <3BD94D81.E18B1985@earthlink.net>
Peter Drechsler wrote:
>
> # Hi,
>
> # I have images (gifs) in a mysql-database running under linux 2.4.0.
> # I want to print them via the CGI module of Perl (v5.6.1) in
> # netscape.
> #
> # What I got from the the db is the images in a scalar.
>
> # Above here is all the db stuff, connection etc: works
> # In column pict defined as blob is the gif
> # After SQL.... I got my image in a scalar.
>
> my $ref = $sth->fetchrow_hashref();
> my $image = $ref->{'pict'};
>
> # So far, so good.
>
> # I can write them in a file and the file is
> # ok and show it in netscape.
> # A temp-file doesn't work
> # and I don't wan't to have a permant (say: redundant) file.
>
> my $anz = CGI->new();
> print $anz->header(), $anz->start_html();
>
> print img{src => $image}; # <--- NOT WORKING
>
> print $anz->end_html;
You don't need CGI.pm for this:
print "Content-type: image/gif\n\n";
binmode STDOUT;
print $ref->{pict};
However, that doesn't mean you can't use it:
binmode STDOUT;
my $boundary = rand(1_000_000) . rand(1_000_000) . rand(1_000_000);
my $id = pack("H4H8",$$,time) . "@" . $ENV{SERVER_NAME};
print header(q[Content-type: multipart/related;
boundary=$boundary; type=text/html]);
print ($boundary = "\015\012--$boundary\015\012");
print header, start_html;
print h1("Here's your image:");
print img {src => "cid:$id"};
print h1("Isn't this cool!");
print end_html, $boundary;
print header {content_type=>"image/gif", content_id=>"<$id>"};
print $image
print $boundary;
__END__
AFAIK, this is kinda sorta how html email with embeded images works,
when the images are included as an attachment.
NB: This code is untested. Also, you should probably be using
Mime::Lite or something to do wonky stuff like this.
--
Klein bottle for rent - inquire within.
------------------------------
Date: 26 Oct 2001 12:22:51 GMT
From: christophe <clelan@tf1.fr>
Subject: problem of connection to a server FTP
Message-Id: <20011026-142251-342092@foorum.com>
hello everybody
i have a problem of connexion to a server FTP
when i run my script (who sould conect to a ftp server) on a IIS server, there
is no problem but when i run this script on a apche server (on a sun), my script
doesn't succed to connect to this FTP server
i connect to this server as
$HOSTSOURCE="IP du serveur FTP";
$LOGINSOURCE=*********;
$PASSWDSOURCE=********;
my $ftp1=Net::FTP->new($HOSTSOURCE,Passive=>1);
--
User of http://www.foorum.com/. The best tools for usenet searching.
------------------------------
Date: Fri, 26 Oct 2001 09:14:01 +0100
From: "jimbo" <jimbo@soundimages.co.uk>
Subject: Re: Regex to swap HTML tags
Message-Id: <4X8C7.1031$l57.5721@NewsReader>
"Logan Shaw" <logan@cs.utexas.edu> wrote
> first tag only has three characters". So, I assumed they were editing
> not arbitrary HTML, but HTML that they have some control over (or at
> least know something about).
Reasonable assumption.
jimbo
;-)
------------------------------
Date: Fri, 26 Oct 2001 11:03:10 GMT
From: "BK" <bkrusch@fakeemail.com>
Subject: Re: Regex to swap HTML tags
Message-Id: <OpbC7.123798$Pr1.31669175@news1.rdc1.tn.home.com>
Thanks for the replies! Yes, the presence of a three character tag precedent
is known.
Much obliged...
"Logan Shaw" <logan@cs.utexas.edu> wrote in message
news:9ra1sm$ma3$1@charity.cs.utexas.edu...
> In article <c6b407df.0110251339.79216e67@posting.google.com>,
> Barry Krusch <bkrusch@yahoo.com> wrote:
> >I want to convert these:
> >
> > <b><li>
> > <i><li>
> >
> >to these:
> >
> > <li><b>
> > <li><i>
>
> Do they always occur adjacent to each other? Do you only want to swap
> those particular pairs of tags?
>
> If so, just do this:
>
> $foo =~ s/<b><li>/<li><b>/;
> $foo =~ s/<i><li>/<li><i>/;
>
> If you want to take an three-character tag that occurs before an "<li>"
> and put it after, then do this:
>
> $foo =~ s/(<.>)(<li>)/$2$1/;
>
> Does that answer the question?
>
> - Logan
> --
> "In order to be prepared to hope in what does not deceive,
> we must first lose hope in everything that deceives."
>
> Georges Bernanos
------------------------------
Date: Fri, 26 Oct 2001 09:05:25 GMT
From: "spamfree" <spamfree@sorted2000.net>
Subject: Security- Upload scripts
Message-Id: <pH9C7.5443$lp2.792879@news1.cableinet.net>
Hi,
I'm wanting to modify a simple upload script.
Any recommended resources/tuts on the many security issues using upload
scripts in perl to Unix?
Thanks.
--
millside
_____________
------------------------------
Date: Fri, 26 Oct 2001 09:17:00 +0100
From: "Scott Bell" <news@scottbell.org>
Subject: Splitting text
Message-Id: <AV8C7.670$o56.124930@news2-win.server.ntlworld.com>
I want to split (for example) a line like this into three.
"The quick brown fox jumps over the lazy dog."
I could use this -> ($one, $two, $three)=split(" ",$data); <- to get "The",
"quick" and "brown" but how would I get $three to equal "brown fox jumps
over the lazy dog."?
--
Scott Bell
Email: scott@scottbell.org
The content of this message has been certified 100% correct.
------------------------------
Date: 26 Oct 2001 08:24:37 GMT
From: Bernard El-Hagin <bernard.el-hagin@lido-tech.net>
Subject: Re: Splitting text
Message-Id: <slrn9ti71i.3nk.bernard.el-hagin@gdndev25.lido-tech>
On Fri, 26 Oct 2001 09:17:00 +0100, Scott Bell <news@scottbell.org> wrote:
> I want to split (for example) a line like this into three.
>
> "The quick brown fox jumps over the lazy dog."
>
> I could use this -> ($one, $two, $three)=split(" ",$data); <- to get "The",
> "quick" and "brown" but how would I get $three to equal "brown fox jumps
> over the lazy dog."?
Why don't you read the docs on split?
( $one, $two, $three ) = split( ' ', $data, 3 );
Cheers,
Bernard
------------------------------
Date: Fri, 26 Oct 2001 10:41:47 +0100
From: Paul Boardman <peb@bms.umist.ac.uk>
Subject: Re: Splitting text
Message-Id: <3BD92FDB.D2D5BBC8@bms.umist.ac.uk>
Bernard El-Hagin wrote:
>
> On Fri, 26 Oct 2001 09:17:00 +0100, Scott Bell <news@scottbell.org> wrote:
> > I want to split (for example) a line like this into three.
> >
> > "The quick brown fox jumps over the lazy dog."
> >
> > I could use this -> ($one, $two, $three)=split(" ",$data); <- to get "The",
> > "quick" and "brown" but how would I get $three to equal "brown fox jumps
> > over the lazy dog."?
>
> Why don't you read the docs on split?
Just to add to Bernards comment. You can view information on Perl
functions/modules/documentation using the perldoc command on the command
line of the machine with the Perl instalation.
perldoc -f split
will give useful info on the split function.
perldoc perldoc
For info on the perldoc command
perldoc perl
for a list of perl documents accessible via the perldoc program.
HTH
Paul
------------------------------
Date: Fri, 26 Oct 2001 04:18:59 -0700
From: "Jürgen Exner" <jurgenex@hotmail.com>
Subject: Re: Splitting text
Message-Id: <3bd946a6@news.microsoft.com>
"Scott Bell" <news@scottbell.org> wrote in message
news:AV8C7.670$o56.124930@news2-win.server.ntlworld.com...
> I want to split (for example) a line like this into three.
>
> "The quick brown fox jumps over the lazy dog."
>
> I could use this -> ($one, $two, $three)=split(" ",$data); <- to get
"The",
> "quick" and "brown" but how would I get $three to equal "brown fox jumps
> over the lazy dog."?
From the horses mouth (perldoc -f split):
split /PATTERN/,EXPR,LIMIT
If LIMIT is specified and positive, splits into no more than
that many fields [...]
jue
------------------------------
Date: Fri, 26 Oct 2001 09:40:28 +0100
From: John Imrie <johni@pa.press.net>
Subject: Re: Stripping Duplicates From Arrays
Message-Id: <3BD9217C.5090904@pa.press.net>
Joe Giordano wrote:
> I currently have a script that looks @ a dat file; each line of the dat file
> is split on a colon seperating the line into columns. Each column is then
> put into an array. I want to take out or ignore the duplicate variables in
> the array. I then use each variable in the first array in a loop (So
> unfortunatley each time the script uses the same variable I get the same
> results. What is the best way to achieve this.
>
> Thanks,
>
> Joe
my @dupes = (1,1,2,3,2,5,6,7);
my %temp = map {$_ => 1} @dupes;
my @no_dupes = keys %temp;
------------------------------
Date: Fri, 26 Oct 2001 09:51:58 +0100
From: "Miguel Manso" <mmanso@yahoo.com>
Subject: Re: Stripping Duplicates From Arrays
Message-Id: <pan.2001.10.26.09.51.58.290.6649@yahoo.com>
my @array = (qw/1 1 1 2 3 4 5 5 5 6 7/);
my %hash;
@array = @hash{@array}=();
In article <PaWB7.6375$C7.2592557@news02.optonline.net>, "Joe Giordano"
<joeg@optonline.net> wrote:
> I currently have a script that looks @ a dat file; each line of the dat
> file is split on a colon seperating the line into columns. Each column
> is then put into an array. I want to take out or ignore the duplicate
> variables in the array. I then use each variable in the first array in a
> loop (So unfortunatley each time the script uses the same variable I get
> the same results. What is the best way to achieve this.
>
> Thanks,
>
> Joe
--
Miguel Manso - <mmanso@prodigio.com>
Departamento Técnico
Prodigio - Produções Digitais Online, S.A.
Tel: +351 22 0106000 - Fax: +351 22 0106001
------------------------------
Date: Fri, 26 Oct 2001 05:04:30 -0400
From: Benjamin Goldberg <goldbb2@earthlink.net>
Subject: Re: Stripping Duplicates From Arrays
Message-Id: <3BD9271E.42AC65@earthlink.net>
Joe Giordano wrote:
>
> I currently have a script that looks @ a dat file; each line of the
> dat file is split on a colon seperating the line into columns. Each
> column is then put into an array. I want to take out or ignore the
> duplicate variables in the array. I then use each variable in the
> first array in a loop (So unfortunatley each time the script uses the
> same variable I get the same results. What is the best way to achieve
> this.
#!/usr/local/bin/perl -w
use strict;
my %seen;
while( <> ) {
next if $seen{$_}++;
chomp;
my @data = split /:/;
# do stuff with @data, like:
print join(":", @data), "\n";
}
__END__
The <> thing will open your files for you, if they're listed on the
commandline.
NB: This code is untested.
--
Klein bottle for rent - inquire within.
------------------------------
Date: Fri, 26 Oct 2001 10:53:38 +0100
From: "Miss J.L. Vallance" <jvallanc@hgmp.mrc.ac.uk>
Subject: Subroutines
Message-Id: <3BD932A2.9B6FF447@hgmp.mrc.ac.uk>
Hi all
I have a subroutine inside another subroutine in a perl CGI script.
When I put a print statement in the nested subroutine, nothing is
printed to screen.
Also a pattern match which has been proven to work in what seem the same
conditions in another script, do not work in this script.
I think it might be a scope problem.
Any clues anyone?
Thanks
Jayne
------------------------------
Date: 26 Oct 2001 10:09:21 GMT
From: Bernard El-Hagin <bernard.el-hagin@lido-tech.net>
Subject: Re: Subroutines
Message-Id: <slrn9tid5q.3nk.bernard.el-hagin@gdndev25.lido-tech>
On Fri, 26 Oct 2001 10:53:38 +0100, Miss J.L. Vallance
<jvallanc@hgmp.mrc.ac.uk> wrote:
> Hi all
>
> I have a subroutine inside another subroutine in a perl CGI script.
>
> When I put a print statement in the nested subroutine, nothing is
> printed to screen.
Is the nested sub called? Or is it just *there*.
> Also a pattern match which has been proven to work in what seem the same
> conditions in another script, do not work in this script.
>
> I think it might be a scope problem.
>
> Any clues anyone?
It's difficult to debug code which one can't actually *see*. Please
post the snippet of your script which produces the faulty behaviour
you describe.
Cheers,
Bernard
------------------------------
Date: 26 Oct 2001 10:03:49 GMT
From: rgarciasuarez@free.fr (Rafael Garcia-Suarez)
Subject: Re: Subroutines
Message-Id: <slrn9tid8i.bvo.rgarciasuarez@rafael.kazibao.net>
Miss J.L. Vallance wrote in comp.lang.perl.misc:
> Hi all
>
> I have a subroutine inside another subroutine in a perl CGI script.
>
> When I put a print statement in the nested subroutine, nothing is
> printed to screen.
> Also a pattern match which has been proven to work in what seem the same
> conditions in another script, do not work in this script.
>
> I think it might be a scope problem.
>
> Any clues anyone?
Not if you don't post a little bit of code that demonstrates the
problem ;-)
--
Rafael Garcia-Suarez / http://rgarciasuarez.free.fr/
------------------------------
Date: Fri, 26 Oct 2001 12:36:33 +0200
From: Edwin =?iso-8859-1?Q?G=FCnthner?= <edgue@web.de>
Subject: Tracing ["non-interactive debugging"] like in REXX?
Message-Id: <3BD93CB1.E614060D@web.de>
Hi there,
in REXX it is possible to switch on "tracing" within a
script file.
Then the REXX kernel will print out step by step what
it is doing (to STDOUT). You can pipe the output into a
file - so you end up with a "complete" trace of
your whole program execution - an ideal base to
start debugging with.
With perl, there is the interactive debugger of course.
I am wondering if this debugger can to the same - meaning:
I start something like "perl -c myscript.pl > trace.txt",
perl executes the whole script and prints every single
step into the file.
regards,
eg
------------------------------
Date: 26 Oct 2001 10:46:10 GMT
From: Bernard El-Hagin <bernard.el-hagin@lido-tech.net>
Subject: Re: Tracing ["non-interactive debugging"] like in REXX?
Message-Id: <slrn9tifau.3nk.bernard.el-hagin@gdndev25.lido-tech>
On Fri, 26 Oct 2001 12:36:33 +0200, Edwin Günthner <edgue@web.de> wrote:
> Hi there,
>
> in REXX it is possible to switch on "tracing" within a
> script file.
> Then the REXX kernel will print out step by step what
> it is doing (to STDOUT). You can pipe the output into a
> file - so you end up with a "complete" trace of
> your whole program execution - an ideal base to
> start debugging with.
>
> With perl, there is the interactive debugger of course.
> I am wondering if this debugger can to the same - meaning:
> I start something like "perl -c myscript.pl > trace.txt",
> perl executes the whole script and prints every single
> step into the file.
perldoc perldebug
Search for "The Perl Profiler".
Cheers,
Bernard
------------------------------
Date: Fri, 26 Oct 2001 13:01:54 +0200
From: Edwin =?iso-8859-1?Q?G=FCnthner?= <edgue@web.de>
Subject: Re: Tracing ["non-interactive debugging"] like in REXX?
Message-Id: <3BD942A2.289690FF@web.de>
Bernard El-Hagin wrote:
> Search for "The Perl Profiler".
I think that is not what I am looking for. I am not
interested in profiling data.
Example: I have a rexx script and place
"trace i" in the first line; i start
rexx myscript.rexx 2> trace.txt and in
the end I have a file with content like this:
7 *-* signal=(interpret=value)
>L> "INTERPRET"
>L> "INTERPRET"
>L> "VALUE"
>L> "VALUE"
>O> "0"
*-* )
>L> "INTERPRET"
>L> "INTERPRET"
>L> "PARSE"
>L> "PARSE"
>O> "1"
*-* se)
>V> "1"
>V> "1"
>V> "1"
>V> "1"
>V> "2"
...
What you see here is like switching on the
rexx debugger and go through the WHOLE script
step by step.
A profiler tells me which subs are called
most often - not the same, isnt it?
------------------------------
Date: Fri, 26 Oct 2001 14:37:15 +0200
From: Edwin =?iso-8859-1?Q?G=FCnthner?= <edgue@web.de>
Subject: Re: Tracing ["non-interactive debugging"] like in REXX?
Message-Id: <3BD958FB.BE2AE271@web.de>
OK, I made some progress:
perldoc perldebug [where else ...]
tells me that there are several configurable options,
So setting PERLDB_OPTS to NonStop=1 LineInfo=db.out AutoTrace
is close, but not close enough. It printes out the
lines, but not what is actually executed ... but maybe
I will figure that out ... sooner or later.
------------------------------
Date: Fri, 26 Oct 2001 08:27:17 -0400
From: Benjamin Goldberg <goldbb2@earthlink.net>
Subject: Re: VVP:making a string=string.
Message-Id: <3BD956A5.A3849E16@earthlink.net>
vivekvp wrote:
>
> Hello,
>
> I have a web page that sends the parameter 'head' to a script and put
> it in a varible called $head_number (it is text and numbers). Then I
> try to set it one called $p_str. But get this:
>
[snip]
> It seems my sql statement "SELECT * FROM poheader WHERE
> head_number=$p_str" is not equalling "SELECT * FROM poheader WHERE
> head_number='SGB000096"
>
> Any help?
#!/usr/bin/perl -w
use CGI::Carp qw(fatalsToBrowser);
use strict;
use DBI;
use CGI qw(param *table);
my $p_str = param("head");
my $dbh = DBI->connect( qw( dbi:Oracle:test@test test test ),
{RaiseError => 1} # This is important!
) or die $DBI::errstr;
my $sth = $dbh->prepare("SELECT * FROM poheader WHERE head_number=?");
$sth->execute($p_str);
print header, begin_html;
print begin_table {width=>"100%"};
print Tr th $sth->{NAME};
while( my $row = $sth->fetchrow_arrayref ) {
print Tr td $row;
}
print end_table, end_html;
__END__
Normally, I would test the results of prepare and execute, but since I
have RaiseError turned on, I don't have to -- if they fail, they call
die, and CGI::Carp results in an appropriate message to the browser.
If you plan on removing CGI::Carp [which you usually should, for
production code], add tests for the success of prepare and execute, and
also [after the fetching is done], test if $sth->err is not false, since
it's possible for an error to occur while fetching, too.
With CGI::Carp ommited, the script would look like:
#!/usr/bin/perl -w
use strict;
use DBI;
use CGI qw(param);
unless( my $dbh = DBI->connect( ..... ) {
print header "text/plain";
print "An error occured connecting to the database\n";
print $DBI::errstr;
exit;
} elsunless( my $sth = prepare( ..... ) ) {
print header "text/plain";
print "An error occured preparing the sql statement\n";
print $dbh->errstr;
exit;
} elsunless( $sth->execute ) {
print header "text/plain";
print "An error occured executing the sql statement\n";
print $sth->errstr;
exit;
} elsunless( my $output = $sth->fetchall_arrayref ) {
print header "text/plain";
print "An error occured fetching the query results\n";
print $sth->errstr;
exit;
} else {
undef $sth; undef $dbh;
}
print header, begin_html, table( {width=>"100%"}, Tr [
th( $sth->{NAME} ),
map td $_, foreach @$output
] ), end_html;
__END__
NB: None of this code is tested.
--
Klein bottle for rent - inquire within.
------------------------------
Date: Fri, 26 Oct 2001 09:35:35 +0100
From: John Imrie <johni@pa.press.net>
Subject: Re: Win32 Perl book/software suggestions?
Message-Id: <3BD92057.5000500@pa.press.net>
Frank McKenney wrote:
> A friend provided me with a lot of free assistance on a recent
> customer project. Using the principle that "no good deed goes
> unpunished" (;-), I'd like to put together a package to impress him
> with, and help him learn, Perl.
>
> He's fairly experienced in mainframe and desktop computer
> programming, all the way from APL and FORTRAN through various ASMs
> to his current "favorite" Clipper/FiveWin in the Win32 environment.
>
> I've been learning/using Perl under Linux (SuSE), but I know that
> ports are available for Win32. O'Reilly's "Learning Perl" is a good
> start, but (IMNSHO) it isn't enough in itself to really impress
> someone who is already doing GUI-based programming in another
> environment. Is there a "Perl/GUI for Win9x Programmers" out there
> that might offer this?
Ok the books I'd recomend for your friend are
Learning Perl on Win32 Systems
Randal L Schwatz, Tom Phenix
ISBN 1-565-92324-3
Programming Perl 3rd Eddition
Wall et all
ISBN 0-596-00027-8
Learning Perl/Tk
Nancy Walsh
ISBN 1-56592-341-6
All are published by O'Reilly
The last of the three describes a GUI add on for Perl. which can be got
from CPAN with the following line
perl -MCPAN -e 'install Tk'
or as is usual on Windows systems you have the Active State build
ppm install Tk
HTH
The Pilgrim
------------------------------
Date: 6 Apr 2001 21:33:47 GMT (Last modified)
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Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>
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------------------------------
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