[23206] in Perl-Users-Digest
Perl-Users Digest, Issue: 5427 Volume: 10
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Tue Sep 2 09:05:39 2003
Date: Tue, 2 Sep 2003 06:05:08 -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 Tue, 2 Sep 2003 Volume: 10 Number: 5427
Today's topics:
Calling perl built-in functions (Jon)
Re: Calling perl built-in functions (Anno Siegel)
Re: Calling perl built-in functions <shawn@magma.ca>
Re: Calling perl built-in functions <bigj@kamelfreund.de>
Re: Comments in templates for pack() <nobull@mail.com>
DBD::CSV questions and is there a DBD::XML? <andrew@NOSPAM_andicrook.demon.co.uk>
Re: Extra carriage returns - why? (John Andrews)
Re: Help -- how to execute "computed Perl code" (Anno Siegel)
Re: Help -- how to execute "computed Perl code" <nobull@mail.com>
Re: Help -- how to execute "computed Perl code" (Steve D)
Re: Help -- how to execute "computed Perl code" (Steve D)
Re: Help -- how to execute "computed Perl code" (Sam Holden)
Re: Last number in the array --- access problem --Newbi (Anno Siegel)
looking for a nedit Syntax Pattern file for perl <andrew@NOSPAM_andicrook.demon.co.uk>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@augustmail.com
Re: Redirecting via LWP <someone@somewhere.com>
Re: what are included in metacharacters for regex? (Anno Siegel)
Re: <bwalton@rochester.rr.com>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: 2 Sep 2003 04:12:37 -0700
From: jhayden@usa.com (Jon)
Subject: Calling perl built-in functions
Message-Id: <28769dad.0309020312.58123e52@posting.google.com>
I have a script that parses a file. In this file, I would like to be able to
put in perl build in functions. So, with that in mind, let me give you this
example that doesn't work:
my $function = "print";
my $args = "hello, world";
&$function $args;
It produces:
Undefined subroutine &main::print called
Is there a way to make this work?
Thanks in advance,
Jon
------------------------------
Date: 2 Sep 2003 11:26:08 GMT
From: anno4000@lublin.zrz.tu-berlin.de (Anno Siegel)
Subject: Re: Calling perl built-in functions
Message-Id: <bj1uog$7n3$2@mamenchi.zrz.TU-Berlin.DE>
Jon <jhayden@usa.com> wrote in comp.lang.perl.misc:
> I have a script that parses a file. In this file, I would like to be able to
> put in perl build in functions. So, with that in mind, let me give you this
> example that doesn't work:
>
> my $function = "print";
> my $args = "hello, world";
>
> &$function $args;
>
>
> It produces:
> Undefined subroutine &main::print called
Well, builtins are not subroutines and can't be called as such.
> Is there a way to make this work?
Make it work how? Do you want to change $function and $args so that
"&$function $args" works, or do you want to keep the values in $function
and $args and write a call that works?
Both are possible. Make up your mind.
Anno
------------------------------
Date: Tue, 02 Sep 2003 07:41:31 -0400
From: Shawn Corey <shawn@magma.ca>
Subject: Re: Calling perl built-in functions
Message-Id: <t-2cnfMJ0JlXHMmiXTWJjQ@magma.ca>
Anno Siegel wrote:
> Jon <jhayden@usa.com> wrote in comp.lang.perl.misc:
>
>>I have a script that parses a file. In this file, I would like to be able to
>>put in perl build in functions. So, with that in mind, let me give you this
>>example that doesn't work:
>>
>>my $function = "print";
>>my $args = "hello, world";
>>
>>&$function $args;
>>
>>
>>It produces:
>>Undefined subroutine &main::print called
>
>
> Well, builtins are not subroutines and can't be called as such.
>
>
>>Is there a way to make this work?
>
>
> Make it work how? Do you want to change $function and $args so that
> "&$function $args" works, or do you want to keep the values in $function
> and $args and write a call that works?
>
> Both are possible. Make up your mind.
>
> Anno
From my bag of dirty tricks:
#!/usr/bin/perl
$function='print';
&$function("Hello, world\n");
sub print {
print @_;
}
------------------------------
Date: Tue, 02 Sep 2003 11:20:16 +0200
From: "Janek Schleicher" <bigj@kamelfreund.de>
Subject: Re: Calling perl built-in functions
Message-Id: <pan.2003.09.02.09.20.16.713451@kamelfreund.de>
Jon wrote at Tue, 02 Sep 2003 04:12:37 -0700:
> my $function = "print";
> my $args = "hello, world";
>
> &$function $args;
>
>
> It produces:
> Undefined subroutine &main::print called
>
> Is there a way to make this work?
Well, you can always do the eval workaround:
eval "$function $args";
with some more problems ...
But what's the problem behind the problem you've written to us?
Greetings,
Janek
------------------------------
Date: 02 Sep 2003 12:42:34 +0100
From: Brian McCauley <nobull@mail.com>
Subject: Re: Comments in templates for pack()
Message-Id: <u9bru3bctv.fsf@wcl-l.bham.ac.uk>
tadmc@augustmail.com (Tad McClellan) writes:
> Vlad Tepes <minceme@start.no> wrote:
>
> > But, if I try to use quotes in the comment:
> >
> > my $packed = pack "l/A* # field "firstwd"
> > A*",
>
>
> > I thought
> > everything after the comment-character would be ignored.
>
>
> To be classified as a "comment character" the # must appear
> in _code_.
>
> There is no "comment character" above because the # is
> data rather than code.
This is an over simplification.
The pack template is _code_ but it is not _Perl_ code. It is (like
regex, sprintf templates and formats) a built-in small language that
is embedded in Perl.
The # character in a pack template is a comment character. But it is
not a Perl comment character.
In the case of pack and sprintf the template code is simply data at
the Perl level. (This is also true of non-builtin small languages
often used in Perl like SQL and XPath and Bourne shell). The Perl code
is parsed according to the usual Perl expression rules to generate a
string (data) and only then is the result interpreted as pack code.
On the other hand, in the case of formats and regex the parsing of the
two languages is more intermingled so I think Tad was hasty in junping
on the OP for not fully appreciating the distinction between code and
data in the case of pack().
--
\\ ( )
. _\\__[oo
.__/ \\ /\@
. l___\\
# ll l\\
###LL LL\\
------------------------------
Date: Tue, 2 Sep 2003 12:00:50 +0100
From: "Andrew Crook" <andrew@NOSPAM_andicrook.demon.co.uk>
Subject: DBD::CSV questions and is there a DBD::XML?
Message-Id: <bj1t0q$o5l$1$8300dec7@news.demon.co.uk>
I wish to save and read data to a CSV or XML file.
manual coding could have problems with multiple writes on a file at the same
time, unless
flock or "\block" are used.
I was hoping that DBD:CSV would take this in to account. But I recently
read:
"I have heard of cases where mod_perl processes block back waiting for their
lock on the CSV, and
once all the Apache children are blocking the server stops responding."
I was wonder if anyone had experience running such a setup and could
comment.
DBD::CSV sounds the best overall solution module wise as it offers SQL
functionality.
Also does anyone know of a DBD::XML module?
regards
Andrew
------------------------------
Date: 2 Sep 2003 01:19:24 -0700
From: john.andrews1@talk21.com (John Andrews)
Subject: Re: Extra carriage returns - why?
Message-Id: <fc134cb0.0309020019.437b6e15@posting.google.com>
Yes, you guys are all correct, I do have problems with my line
endings (caused by files originally created on a mac, then a
revision control server doing something 'clever' when
files are checked out)
Thanks
------------------------------
Date: 2 Sep 2003 10:56:55 GMT
From: anno4000@lublin.zrz.tu-berlin.de (Anno Siegel)
Subject: Re: Help -- how to execute "computed Perl code"
Message-Id: <bj1t1n$7n3$1@mamenchi.zrz.TU-Berlin.DE>
Steve D <google.deller@smsail.com> wrote in comp.lang.perl.misc:
> My code dynamically creates a scalar with a text string that is a
> valid Perl code line.
>
> How can I get Perl to execute the line contained in that scalar?
>
> I could write it to a temp file and then "do <file>", but I want to
> avoid that overhead. It does not seem eval and "do BLOCK" are the
> answer.
"eval" is the answer, in the string-eval form. What have you tried?
Anno
------------------------------
Date: 02 Sep 2003 12:24:43 +0100
From: Brian McCauley <nobull@mail.com>
Subject: Re: Help -- how to execute "computed Perl code"
Message-Id: <u9ekyzbfgk.fsf@wcl-l.bham.ac.uk>
google.deller@smsail.com (Steve D) writes:
> My code dynamically creates a scalar with a text string that is a
> valid Perl code line.
This is a powerful technique but one that should only be used in very
special circumstances.
Unlike some of the regulars here I'm not gripped by a rabid fear of
this technique, indeed I embrace it. But before you use it you must
understand how parsing data as code can easily produce obscure hidden
bugs or security holes.
> How can I get Perl to execute the line contained in that scalar?
>
> It does not seem eval [is] the answer.
Why? (Oh and don't forget #line)
> Any good solutions?
Dunno. The solution you have rejected (for no apparent reason) is the
solution to your "Y" but there's a fairly good chance it's not a good
solution to your "X"[1].
Since you do not tell us anything about your "X" we can't advise on a
good solution.
[1] An "XY" problem is where you want to do "X" but ask "How do I do
Y?" because you think that doing "Y" is part of doing "X" but actually
doing "Y" is something more complex/riskly/whatever than the direct
solution to doing "X".
--
\\ ( )
. _\\__[oo
.__/ \\ /\@
. l___\\
# ll l\\
###LL LL\\
------------------------------
Date: 2 Sep 2003 05:03:27 -0700
From: google.deller@smsail.com (Steve D)
Subject: Re: Help -- how to execute "computed Perl code"
Message-Id: <e41b2b3b.0309020403.5f6e515e@posting.google.com>
James Willmore <jwillmore@cyberia.com> wrote in message news:<20030901233005.2ce3cef3.jwillmore@cyberia.com>...
> On Tue, 02 Sep 2003 02:54:28 GMT
NOPE. Your "solution" requires the code text to be known at COMPILE
time.
I need to compile code text that has been create at RUN time. The
following is a complete program example of what I want to do (the
@code_text is just a simple way to define strings -- in reality they
are composed from much more complex circumstances).
As I said, I *could* write @code_text to a file, then "do <file>" to
get the effect I need, but want to avoid writing and reading a file
just to get evaluation of the code.
Regards,
Steve
#! /bin/perl
use strict ; use warnings ;
my $a = 1 ;
my @code_text = ( '$a += 3 ;', '$a /= 2 ;', 'print $a ; ' ) ;
for my $code_text ( @code_text ) {
my $code = sub { $code_text } ;
print "$code_text\n" ;
# DOES NOT WORK
# I want to evaluate the "code" contained in $code_text
# NOT the "value" of $code_text. $a should get 3 added,
# then be divided by 2, and then printed.
$code->() ;
} ;
print "$a should be 2 ( 1 plus 3 divided by 2 )\n"
------------------------------
Date: 2 Sep 2003 05:20:39 -0700
From: google.deller@smsail.com (Steve D)
Subject: Re: Help -- how to execute "computed Perl code"
Message-Id: <e41b2b3b.0309020420.77347cc4@posting.google.com>
James Willmore <jwillmore@cyberia.com> wrote in message news:<20030901233005.2ce3cef3.jwillmore@cyberia.com>...
> On Tue, 02 Sep 2003 02:54:28 GMT
> James Willmore <jwillmore@cyberia.com> wrote:
> > On 1 Sep 2003 18:41:31 -0700
> > google.deller@smsail.com (Steve D) wrote:
> > > My code dynamically creates a scalar with a text string that is a
> > > valid Perl code line.
James,
Your code gave me some ideas. Some more experimentation did finally
come up with a solution:
#! /bin/perl
use strict ; use warnings ;
my $a = 1 ;
my @code_text = ( '$a += 3 ;', '$a /= 2 ;', 'print "$a\n" ; ' ) ;
for my $code_text ( @code_text ) {
my $code = sub { eval "$code_text" } ; # Just need eval to make it
work
print "Executing $code_text\n" ;
$code->() ;
} ;
print "$a should be 2 ( 1 plus 3 divided by 2 )\n"
=================================
The eval in the sub def is the key. I had tried a do of an eval, an
eval of an eval, but never a sub of an eval. That's the key.
Thanks for your help.
Regards,
Steve
------------------------------
Date: 2 Sep 2003 12:22:23 GMT
From: sholden@flexal.cs.usyd.edu.au (Sam Holden)
Subject: Re: Help -- how to execute "computed Perl code"
Message-Id: <slrnbl92rv.qrg.sholden@flexal.cs.usyd.edu.au>
On 2 Sep 2003 05:03:27 -0700, Steve D <google.deller@smsail.com> wrote:
[snippage]
> # I want to evaluate the "code" contained in $code_text
^^^^
And that is what you should do...
(and make sure you understand the risks associated with executing
arbitrary code).
--
Sam Holden
------------------------------
Date: 2 Sep 2003 12:52:44 GMT
From: anno4000@lublin.zrz.tu-berlin.de (Anno Siegel)
Subject: Re: Last number in the array --- access problem --Newbie question
Message-Id: <bj23qs$7n3$4@mamenchi.zrz.TU-Berlin.DE>
Tore Aursand <tore@aursand.no> wrote in comp.lang.perl.misc:
[...]
> From what I understand, you just want the last column for the last row?
> In that case, you should first get the last row, then the last column
> for that row;
>
> my @rows = <MAER_FILE>;
> my $last = $rows[-1];
> my @cols = split( /\s+/, $last );
>
> The code above is just an example of how you should think. The actual
> solution might differ a little; you should seriously think about how big
> the file you're reading is, as 'my @rows = <MAER_FILE>;' throws the
> whole file into memory.
The slurping can easily be avoided:
my $last;
$last = <MAER_FILE> until eof( MAER_FILE);
Or use File::ReadBackwards from CPAN.
Anno
------------------------------
Date: Tue, 2 Sep 2003 12:24:54 +0100
From: "Andrew Crook" <andrew@NOSPAM_andicrook.demon.co.uk>
Subject: looking for a nedit Syntax Pattern file for perl
Message-Id: <bj1udl$puf$1$8300dec7@news.demon.co.uk>
looking for a nedit Syntax Pattern file for perl
can anyone help?
many thanks
Andrew
------------------------------
Date: Tue, 02 Sep 2003 02:23:14 -0500
From: tadmc@augustmail.com
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.4 $)
Message-Id: <4bmcnbSz-qz_2MmiXTWJjA@august.net>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
- Do not provide too much information
- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
- Beware of saying "doesn't work"
- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.4 $)
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
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http://andrew2.andrew.cmu.edu/rfc/rfc1855.html
A note to newsgroup "regulars":
Do not use these guidelines as a "license to flame" or other
meanness. It is possible that a poster is unaware of things
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Do *NOT* send email to the maintainer of these guidelines. It will be
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Before posting to comp.lang.perl.misc
Must
This section describes things that you *must* do before posting to
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have others do your work.
The perl distribution includes documentation that is copied to your hard
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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
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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
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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
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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
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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 expected in all newsgroups. Lurking means
to monitor a newsgroup for a period to become familiar with local
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"
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These sections describe how you can help keep your article from being
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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
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It should be understood that you may not know that the root of your
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Operating System related), so off-topic postings will happen from
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Carefully choose the contents of your Subject header
You have 40 precious characters of Subject to win out and be one of
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Spend them indicating what aspect of Perl others will find if they
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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
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Use an effective followup style
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Intersperse your comments *following* each section of quoted text to
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"TOFU".
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
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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
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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: Tue, 2 Sep 2003 11:01:37 +0100
From: "Bigus" <someone@somewhere.com>
Subject: Re: Redirecting via LWP
Message-Id: <bj1pq3$iu4@newton.cc.rl.ac.uk>
"James Willmore" <jwillmore@cyberia.com> wrote in message
news:20030901151911.3612309c.jwillmore@cyberia.com...
> On Mon, 1 Sep 2003 18:41:57 +0100
> "Bigus" <bigus_34@yahoo.co.uk> wrote:
> > I'm not storing a file, no.. the directory I want the user to end up
> > in is displayed via Apache's directory listing feature.. ie: there
> > is no html page in that directory. If I have to start creating &
> > storing temp files then it could be a bit of a pain. There are about
> > a thousand directories that will be handled by this script.
> >
> > Can anyone give me any further pointers on what to search for?
>
> Why are you using LWP in a CGI script? If you are using Apache's
> directory listing, what are you listing, if not files? What exactly
> are you tring to do?
Well, you've solved it for me (see below), but just for the sake of
completeness, as I evidently didn't explain what I was doing very well -
basically, each directory is a file area associated with a Listserv mailing
list. The directory is password protected by an Apache htaccess file to stop
users typing a URL and getting there directly. My CGI script makes them log
into Listserv and checks to make sure they are a subscriber (or a site
administrator) to the mailing list that they are trying to access the file
area of. If they pass those checks the script takes them to the file area,
automatically dealing with the Apache authentication.
> In your OP, you wanted to do redirection. Then why not
> 1) use the CGI module's redirect method
> 2) simply print the proper header (print "Location: <new URL>\n\n";)
That worked! I love simple solutions, and that helped fill in a gap in my
knowledge of something that I should probably know by now :)
Many thanks
Bigus
------------------------------
Date: 2 Sep 2003 11:46:42 GMT
From: anno4000@lublin.zrz.tu-berlin.de (Anno Siegel)
Subject: Re: what are included in metacharacters for regex?
Message-Id: <bj1vv2$7n3$3@mamenchi.zrz.TU-Berlin.DE>
http://ejobseek.com <_@_._> wrote in comp.lang.perl.misc:
Don't top-post.
> the example in perlfaq is:
>
> How can I quote a variable to use in a regex?
> The Perl parser will expand $variable and @variable references
> in regular expressions unless the delimiter is a single quote.
> Remember, too, that the right-hand side of a "s///" substitution
> is considered a double-quoted string (see perlop for more
> details). Remember also that any regex special characters will
> be acted on unless you precede the substitution with \Q. Here's
> an example:
>
> $string = "to die?";
> $lhs = "die?";
> $rhs = "sleep, no more";
>
> $string =~ s/\Q$lhs/$rhs/;
> # $string is now "to sleep no more"
>
> Without the \Q, the regex would also spuriously match "di".
>
>
> I DON'T UNDERSTAND WHY DI IS MATCHED!
Yelling doesn't help understanding, analysis does.
It doesn't match "di". The error is that /die?/ matches "die" without
matching the final "?". It can't match "?" because there is no "?" in
the regex. The "?" makes the final "e" in "die" optional (but it is
matched anyhow).
[tofu snipped]
Anno
------------------------------
Date: Sat, 19 Jul 2003 01:59:56 GMT
From: Bob Walton <bwalton@rochester.rr.com>
Subject: Re:
Message-Id: <3F18A600.3040306@rochester.rr.com>
Ron wrote:
> Tried this code get a server 500 error.
>
> Anyone know what's wrong with it?
>
> if $DayName eq "Select a Day" or $RouteName eq "Select A Route") {
(---^
> dienice("Please use the back button on your browser to fill out the Day
> & Route fields.");
> }
...
> Ron
...
--
Bob Walton
------------------------------
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 5427
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