I'd make an untaint function that took the param() name, a regex to use,
and a default value to use.

sub untaint {
my ($name, $rx, $default) = @_;
my $ok = $query->param($name) =~ $rx ? $1 : $default;
$query->param($name, $ok);
}

You use it like so:

my $MOSIAC_SCALE = untaint('MOSIAC_SCALE', qr/(d+)/, 20);
# etc.

As for your code:

You should *never* use $DIGIT variables after a regex unless you're sure
the regex *matched*.

--
Jeff "japhy" Pinyan % How can we ever be the sold short or
RPI Acacia Brother #734 % the cheated, we who for every service
http://japhy.perlmonk.org/ % have long ago been overpaid?
http://www.perlmonks.org/ % -- Meister Eckhart

Do all the 30 parameters need to be validated in the form of
untainting? For params that will not be used directly in system
operations, you may want to consider something simpler.

Personally I like to populate a hash with the CGI input, and assuming
that has been done, and that you don't need to reassign the parameters
in the CGI object, you could for instance do:

$in{MOSAIC_SCALE} =~ /^d+$/ or $in{MOSAIC_SCALE} = 20;

or even just:

$in{MOSAIC_SCALE} ||= 20;

For params that need untainting, I like Jeff's suggestion.

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

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You can't. But you can store a *reference* to an array in a scalar.

This will work:

# the backslash ("") returns a reference to the
# variable, so this doesn't actually pass the array,
# it passes a reference (pointer sort of) to the array.
goodsub(@array, $scalar);

sub goodsub()

{
my ($array_ref,$scalar) = @_;

# turns the ref back to an actual array.
my @array = @{$array_ref};

# or use the array directly through the ref.
# note that changes made through a ref will change
# the original array.
print $array_ref->[0];
}

No, not the way you intend. You could use only references, but that
wouldn't make sense.

Rob

-----Original Message-----
From: gohaku [mailto:[Email Removed]]
Sent: Sunday, July 18, 2004 8:59 PM
To: Perl Beginners
Subject: Another Perl datatype headache ( scalars $, hashes %, and
arrays @ )


Hi everyone,
after writing perl scripts for about 3 years now, I still have trouble
with the
basic datatypes.
I know that variables that start with '$' are scalars.
This covers Hashes ($HASH{$key}), Arrays ( $_[0] ), and
regular scalar values ( $foobar );

The code I write as well other's code is still unreadable to me
even though I have followed examples from the
Camel book, many other Perl books from O'Reilly and online references.
I have also used perldoc on many occasions.

There are still some things that haven't sunk in, such as:

If I want to add Hash keys to another Hash, I do the following:

%HASH = ( 1 => 'one' ); #NO BRACES OR ELSE....
%HASH2 = ( 2 => 'two' ); AGAIN, NO BRACES OR ELSE...
@HASH2{ keys %HASH } = "";
#confusing, considering it's the symbol used for arrays

To get the length of an array, it's $#array, not #@array or #$array.
Usually, I use scalar @array;

Problems with subroutines where the array is the first argument
sub badsub()

{

my (@array,$scalar) = @_;
#Pass Array last!
#my ($scalar,@array) = @_:
...
}

I still don't know how to declare arrays using only '$' instead of '@'

anyway, Is it possible to write scripts using only '$' instead of other
prefix symbols?
In other words, a php-style script written in perl

Thanks in advance.
-gohaku


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Yes I did, and I'll do so again. You said that Vars() must be called in
list context, not scalar context. That is false, and the fact that it is
false is clearly documented in 'perldoc CGI' - a document you clearly
are not familiar with.

Further, you claimed that the OP called Vars() as a function, but the
code he posted read 'my $params = $q->Vars()' - clearly you don't know
the difference between a function and a method.

Mark asked for help. The error he received is "Undefined subroutine";
calling Vars() in scalar context will not produce that error, and
neither will calling Vars() as a method when it has also been imported
as a function.

Calling Vars() as a function *will* produce that error, if it has not
been imported as a function. But in the code Mark posted, it *is*
imported; not only that, it's called as a method. Doing both is wrong
only in terms of style - it won't cause an error.

You were wrong on at least one point, and overall your suggestions were
useless. Calling me rude won't change those facts.

sherm--

--
Cocoa programming in Perl: http://camelbones.sourceforge.net
Hire me! My resume: http://www.dot-app.org

Thanks for posting your advice which I have taken on board. Much of the
comments are moot now anyway as I emailed my host support who told me they
don't even have CGI::Vars installed anyway and won't do it (cheapskates!).
So all the code posted probably *should* work if that were not the case.
Hence the error message and my earlier suspicions were correct. I've opted
for changing the way I post my variables from the PHP server so I don't need
to use Vars just param().

[snip]

I totally agree with you. I wish some people would try to remember what it
was like when *they* first started learning to code. It's this kind of
attitude that puts people off Usenet and totally negates any helpfulness of
the comments being offered. I tend to avoid people who post comments like
this as they often just need their egos massaged by being able to patronise
newbies. Thankfully there are people like yourself who are genuinely trying
to help people starting out in code and not just show-boating.

Thanks.
Mark

Hi

I have tried your code and it works...

This does not happen to me :-|

Are you sure the problem is in that piece of code? Have you tried
separating it from the rest of code and test it alone? Because that's
what I've done and it works... $val has always been 0 :-|

HTH,

jac

Jos Alves de Castro <[Email Removed]>
http://natura.di.uminho.pt/~jac

Don't do that.

HTML is tremendously difficult to analyze properly with tools like
regular expressions.

You're much, much better off using a proper parser library that can
build up a tree model of the html that you can analyze as you like.

The standard libraries for this are probably HTML::Parser and
HTML::Treebuilder. You may also like HTML::TableContentParser.

<http://search.cpan.org/~gaas/HTML-Parser-3.36/Parser.pm>
<http://search.cpan.org/~sburke/HTML-Tree-3.18/lib/HTML/TreeBuilder.pm>
<http://search.cpan.org/~sdrabble/HTML-TableContentParser-0.13/TableCont
entParser.pm>

This may point you in a useful direction:

use HTML::TableContentParser;
$p = HTML::TableContentParser->new();
$html = read_html_from_somewhere();
$tables = $p->parse($html);
for $t (@$tables) {
for $r (@{$t->{rows}}) {
print "Row: ";
for $c (@{$r->{cells}}) {
print "[$c->{data}] ";
}
print "n";
}
}

Something like this should work even for godawful ms-html :-)

It looks like HTML::TableContentParser makes sorting through the
structure of the table pretty easy; HTML::Parser could go farther by
reducing it down to just the printable text -- some combination of the
two may be useful here.

Once you've stripped out all the junk (all the span tags, the paragraph
tags, the "<o:p></o:p>" type debris, etc), you just need to do convert
the html structure into some kind of populated data structure.

You didn't give enough of the html to suggest what the rest of the table

is structured like -- it was really just one big hairy table cell -- so
it's hard to guess how the other pieces fit together.

Can you post a simpler example of what the table is built like, e.g.:

+------------+-------+---------------+----------------+
| priority 1 | field | another field | some more |
+------------+-------+---------------+----------------+
| priority 3 | field | any data here | other things |
+------------+-------+---------------+----------------+
| priority 2 | field | stuff stuff | whatever |
+------------+-------+---------------+----------------+

Or is it more complcated than that?



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by Henry Mancini
from 'The Best Of Mancini'

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Aha, the keys have the same name.. Good! Then Randy's suggested code
should do.

As regards documentation, besides "perldoc -f sort", there is a FAQ
entry that is very much applicable to this problem: "How do I sort an
array by (anything)?"

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

No. You could store the data used to generate the struct, and then use
it later.

my @struct_data = [
key1 => 'type',
key2 => 'type',
];

struct Name => @struct_data;

then iterate of @struct_data...

If you're using version 5.8 or later you can use restricted hashes. See
`perldoc Hash::Util`

Randy.

Okay. If I understand you correctly, you don't need any additional
keys to be able to sort by number of elements in the arrays, since
that info is still conveniently available.

my %HoA = (
'15.' =>
[ 'AGCGGGGAG','AGCGGGGCG','AGCCGGGCG','AGCCAGGAG' ],
'16.' =>
[ 'AGCGGAGCG','AGCCGAGGG','AGCGGAGGG' ],
);

print "Sorted by keysn";
for ( sort { $a <=> $b } keys %HoA ) {
print "$_: @{ $HoA{$_} }n";
}

print "n";

print "Sorted by number of elementsn";
for ( sort { @{ $HoA{$a} } <=> @{ $HoA{$b} } } keys %HoA ) {
print "$_: @{ $HoA{$_} }n";
}

--
Gunnar Hjalmarsson
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did you meant:

my $struct_data = [ #array_ref
key1 => 'type',
key2 => 'type',
];

struct Name => $struct_data;
then iterate of @$struct_data ...

?

array = array_ref is confusing to me ...
could you explain please ?

helpfull module !
Hash vivification is a nightmare, really ...

Jos.

What have you done to find out?

perldoc -f sort
perldoc -q "sort an array"

I think you also need to read up on data structures:

perldoc perldsc

This is one suggestion:

print "Sorted by ic valuen";
for my $hashref ( sort { $a->{ic} <=> $b->{ic} } @AoH ) {
print "$hashref->{ic}: @{ $hashref->{values} }n";
}

print "n";

print "Sorted by number of elementsn";
for my $hashref ( sort {
@{ $a->{values} } <=> @{ $b->{values} }
} @AoH ) {
print "$hashref->{ic}: @{ $hashref->{values} }n";
}

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

Can you send a file example.

Don't considering the file size.

use Data::Dumper;
my @file = split(/(2.2./d+./d+./d+) /, $fileText);
shift(@file);
my %blocks = @file;
print(Dumper(%blocks));

In blocks you would find the keys read to be parsed and the values as being
the rest.

One real example cloud help.

Marcos

I know this isn't getting into the spirit of things, but have you
considered simply using the `units` program?

% units
500 units, 54 prefixes
You have: 59443 bytes
You want: megabytes
* 0.056689262
/ 17.640025
You have: 59443 bytes
You want: kilobytes
* 59.443
/ 0.016822839
You have: ^C
% units bytes kilobytes
* 0.001
/ 1000

% units bytes megabytes
* 9.5367432e-07
/ 1048576

The nice thing about `units` -- in this context -- is that it lets the
user pick the conversion units they want to work with, and also gives
hints for converting both to & from the alternate measurement scale.

Of course, working this into a larger program that does other things
might be annoying -- in which case your way is better -- but if all you
want is the conversions, this is a solved problem :-)


--
Chris Devers

What have you got so far? Where are you stuck? Getting user input
(where from)? Working out which order of magnitude the number is?
Converting between kilo and mega et al? Showing the output?

Show us some code.

--
David Dorward
<http://dorward.me.uk/>
<http://blog.dorward.me.uk/>

heh, that was exactly what i'm looking for, thanks. ugh, now i gotta
rewrite 3 days worth of code with restricted hashes instead of
Class::Struct ...=/

Inside of a subroutine "shift" with no arguments is the same as "shift @_" and
outside of a subroutine "shift" with no arguments is the same as "shift
@ARGV". You can read all about subroutines in the perlsub document.

perldoc perlsub



John
--
use Perl;
program
fulfillment

You're making perfect sense - the problem is not as trivial as I thought
originally, but I think it's not that bad as long as you don't require a
precision of 100%.

In a perl script I wrote some time ago, I'm grouping log messages by comparing
them word by word, using the String::Compare module like this:

compare($message1, $message2, word_by_word => 5);

If I read the module's code correctly, the strings are split up by whitespace
and then compared char by char. Using this approach, I get a high similarity
even if the differing parts of the strings do not have the same length, like
in
failed to connect to primary server
failed to connect to secondary server

What I did now was to extend String::Compare in a way that it records the
differing parts of the strings in a string array for each string (actually, I
did not extend String::Compare, but ported it to Java, because I'm writing
the application in Java, but the idea should be the same) and returns a
"wildcarded" version of the string, i.e. a version that replaces each
character that is not identical in both strings with a wildcard string.

Currently, I'm not using the regexp that is generated in this way for matching
new messages, because I ran in some kind of deadlock: What should I do when I
get a message for which I do not have a matching regexp yet? Since I do have
only one occurence of this message so far, I can not detect a pattern, thus I
can not generate a regexp. Therefore, I've got to compare all messages that
follow in the method described above against the real messages, not against a
wildcarded version.
Anyway - if you choose the wildcard-character wisely, I think you should be
able to generate a regexp that is surely not as good as one written by a
human, but probably good enough (e.g. you could take
(.*?)
as wildcard character for each differing "word").

At the moment, this should be enough to solve my problem - I'm already using
the word-by-word string comparison successfully, and it looks as if the
ported/extended java version of String::Compare would do what I need.
Nevertheless I could imagine that you could build better regexps by comparing
the data that you extracted from the message (since I need to extract the
data anyway to use them later, this is a very likely option). Let's say I've
got the following log messages taken from a web application:

30/08/2004 23:25:01 processed request for a.html - took 35 ms
30/08/2004 23:25:05 processed request for ab.html - took 42 ms
30/08/2004 23:25:05 processed request for a.html - took 37 ms

My application compares the messages, detects that they are very similar, and
creates the following pattern (assuming that the wildcard char is an asterisk
and that a multi-character difference is replaced by one wildcard char):

30/08/2004 23:25:* processed request for *.html - took * ms

The differing data it extracts for the three lines is this:

01 a 35
05 ab 42
05 a 37

Going over the individual "columns" of data, the application could try to
match some pre-declared data formats, i.e. it could check if all values match
certain patterns like "d+", "[azAZ]+" etc. If it finds a matching format, it
could adapt the regexp so that it matches more fine-grained.

You could object (and if I understood your mail correctly, you already did)
that the application created a wrong pattern by taking the date (including
the minutes, but not the seconds) as fixed - a log message that arrives a
minute later would not fit the regexp anymore. This is a problem if I'm
trying to use the regexp to match the messages, but not if I'm comparing the
messages as strings again (as described above).

Writing this, I think you're right - my problem is probably not solvable by
generating regexps on the fly, but only (hopefully) by comparing strings on a
more brute-force level. It might be an option to try to use regexps in order
to speed up the process, but if you do not find a matching regexp, you
probably need to go back to comparing strings again...

I've not finished the application yet, so I can't say if all of this is going
to work, but I'm quite optimistic at the moment. With a bit of luck, I can
show you a working version in a few weeks (FWIW: The application I'm talking
about will be a log4j server application - similar to chainsaw, but built for
the application operators as opposed to the developers).

Thank you for your insightful questions and suggestions - I appreciate
very much the opportunity to discuss those problems before running against too
many walls. :-)

Philipp

You realize, of course, that this can be done entirely in Perl ?

Quoting from the excellent _Perl Cookbook_:

[...] you can emulate wc by opening up and reading the file yourself:

open(FILE, "< $file") or die "can't open $file: $!";
$count++ while <FILE>;
# $count now holds the number of lines read

Another way of writing this is:

open(FILE, "< $file") or die "can't open $file: $!";
for ($count=0; <FILE>; $count++) { }

If you're not reading from any other files, you don't need the $count
variable in this case. The special variable $. holds the number of
lines read since a filehandle was last explicitly closed:

1 while <FILE>;
$count = $.;

This reads all the records in the file and discards them.

But if you really do need to do this via a system command -- you don't,
but I'll play along -- then the command as you've given it is what is
known as a Useless Use Of Cat.

This command --

cat file | wc -l

-- is equivalent to this one --

wc -l file

-- but the latter invokes less overhead, and so should be a bit faster.

Unless you really are conCATenating a chain of files together, most
commands of the form "cat foo | cmd" can be rewritten as "cmd foo" or,
maybe, "cmd < foo".



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by Kermit
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--
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where to stand.
Larry Wall
---

( |

You realize, of course, that this can be done entirely in Perl ?

Quoting from the excellent _Perl Cookbook_:

[...] you can emulate wc by opening up and reading the file
yourself:

open(FILE, "< $file") or die "can't open $file: $!";
$count++ while <FILE>;
# $count now holds the number of lines read

Another way of writing this is:

open(FILE, "< $file") or die "can't open $file: $!";
for ($count=0; <FILE>; $count++) { }

If you're not reading from any other files, you don't need the
$count
variable in this case. The special variable $. holds the number of
lines read since a filehandle was last explicitly closed:

1 while <FILE>;
$count = $.;

This reads all the records in the file and discards them.

But if you really do need to do this via a system command -- you don't,
but I'll play along -- then the command as you've given it is what is
known as a Useless Use Of Cat.

This command --

cat file | wc -l

-- is equivalent to this one --

wc -l file

-- but the latter invokes less overhead, and so should be a bit faster.

Unless you really are conCATenating a chain of files together, most
commands of the form "cat foo | cmd" can be rewritten as "cmd foo" or,
maybe, "cmd < foo".



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np: 'It's Not Easy Being Green (lo-fi midi version)'
by Kermit
from 'The Muppet Movie Soundtrack'




Chris,

You are exactly right, that is a useless use of cat, old habits die
hard. And of course you are correct in that it can be done entirely in
perl, the availability of the shell cmd wc makes us lazy, and we don't
want to code what we can just call from the system.

Chris Hood

Except laziness is a virtue, this is just insufficient code, not the
"good" laziness. If you coded it up the way it *should* be done for
portability, security, proper error handling, etc. it would in the end
be longer.

my @array;
tie @array, 'Tie::File', $filename or die "Can't tie file: $!";
my $length = @array;

Tough to beat....

http://danconia.org

You can't.
You can make it unreadable to most, you can make it more or less hard
to others, but you can't do anything to prevent a seasoned Perl
hacker to get to see your code.

You want to go to
http://www.perlmonks.org/index.pl?node=Super%20Search
and search for "hide script source". This has been discussed quite a
few times on PerlMonks.

Jenda
===== [Email Removed] === http://Jenda.Krynicky.cz ====When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery

I don't know the first thing about ASP programming, sorry.

You can try the [Email Removed] list, but I don't know how much
expertise they would have with ASP either...


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Chris Devers [Email Removed]
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np: 'Movin' Right Along (lo-fi midi version)'
by The Muppets
from 'The Muppet Movie Soundtrack'

Hmm, not sure what you mean by "client side". Both ASP and Perl are
server-side technologies.

Anyway, you might want to start at http://perl-xml.sourceforge.net/faq/

OK, well the faq I pointed you to will give you some ideas of the overall
topic of parsing XML with Perl. Lots of ways to approach it, so get an
overview before diving in.

If you're using Apache, there's no reason to use ASP if you don't have
to; this should work with straight Perl/CGI or mod_perl instead.

Would doing this as a regular CGI script be an option for you? You'll
probably have much better luck finding help if you can do that...


(Also, it's "Perl" for the language, "perl" for the program that runs
scripts written in the language, and never ever "PERL" for anything.)



--
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np: 'It's Not Easy Being Green (lo-fi midi version)'
by Kermit
from 'The Muppet Movie Soundtrack'

It would be much easier using XML::Simple.

...
use XML::Simple;

my $data = XMLin('CustomSkins.xml');
print $data->{to};
...

Jenda
(Code is untested but should be about right.)

===== [Email Removed] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery

Please send us
1. the complete ASP you have
2. the exact errors you get
3. your operating system version, your web server version, your perl
version (run perl -v from command prompt)

Jenda
===== [Email Removed] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery

Sorry for the delay :)

Yep that did it! Thanks :)

That is weird, mine finishes the same either way, just not the right
goodies :)

Have a good one Jenda!

Lee.M - JupiterHost.Net

Here is what I would do:

foreach(@logaray) {
if(m/$conmsg/) { # or # if($_ =~ m/$conmsg/) {

I'm not sure why you're using 'our' verus 'my'?

foreach(@array) { my $msg = $_;

The above does not work because 'eq' is forcing the arrays into scalar
context, therefore you are testing whether the length of the arrays is
string (not numeric that would be C<==>) equal. But how to do this can
be found in the FAQ,

perldoc -q 'test whether two arrays or hashes are equal'

perldoc perlfaq4, has some other juicy bits about analysing arrays and
other data stores.

http://danconia.org

my @files = map { "$images/$_" } grep { !/^./ } readdir IMAGES;

Not sure why you are using @ARGV just for its special qualities (aka the
<> operator) why not name our variables, we are allowed too.

No need to use a while here, since you already have a complete array,

foreach my $file (@files) {

By naming our variables we now see that we are dealing with a filename,
rather than a typeglob reference.

$image->Read(file => $file)

The example you are using assumes that *ARGV contains an opened
filehandle to the file itself, *but* within the loop you are executing
on each line. See perldoc perlop for more. I would skip using the
special nature of the variables until you understand them. Try using
specifically named variables until the program works, then reduce it if
you must.

C<Write> expects a filename argument, not a directory, or a handle.

Not sure why these statements are strung together with C<and> they can
be separate, you haven't really benefited by making them a single
statement. And you wouldn't normally close ARGV.

You can close your dir earlier in the process, since you are done
reading from it.

http://danconia.org

--As for the rest, it is mine.

Don't bother. ;)

It's a number, after all. Perl will remove leading zeros for you, as long
as there are only numbers. Strip out anything that isn't valid, and add
the zero when you need it. (I suggest sprintf, personally.)

Daniel T. Staal

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Either....

It appears that the docs for I::M are incorrect and that C<Read> and
C<Write> must take a filehandle. Difficult to tell since all the code
is XS/C and I didn't feel like popping the hood on it. You could try
switching back to using a handle but I would be more specific about it,
so for instance, within the foreach you would have:

open my $READHANDLE, $filename or die "Can't open file for reading: $!";
$image->Read('file' => $READHANDLE);

etc.

Or there is an issue with the installation, paths, etc. on Windows. You
should retrieve the actual error message from I::M and see what it says,
similar to,

my $result = $image->Read('file' => $filename);
print $result;

Have you checked out the info at:

http://www.dylanbeattie.net/magick/

It appears to be good info for Win32 specific stuff related to I::M.
Personally I can't even test it here so it is difficult for me to point
you in the right direction. Maybe one of the other M$ users will chime
in ...

http://danconia.org

Thanks. We are using WebCT here which has the DBM-technology
embedded. So SQLite is not an option in this case. We will try
AnyDBM.

Regards
Johann
--
Johann Spies Telefoon:
Informasietegnologie, Universiteit van Stellenbosch

"For my thoughts are not your thoughts, neither are
your ways my ways, saith the LORD. For as the heavens
are higher than the earth, so are my ways higher than
your ways, and my thoughts than your thoughts."
Isaiah 55:8,9

Thanks for this, I missed this one.

In case, I am doing something like a log with User v TimesOfSignIn. So, user name will set as 30 char long, and the Signin times is about in scope of a normal integer. I wanna make this a simple DB for this but not a list of single files for each user. So I wanna make this doable for ramdom read write, so, that should be in a binary file. I can't do random read write with a text file anyway, right ? So I don't want to use 'A' or 'a' as pack templates.

However, as the file is in a binary, I think there could be a size benfit for me to compress the data length. Actually, am I on the right point for starrting this ? Any starting hints ? or very simple example perhaprs ?

hehe... sorry for bugging =)
I made this for other copy paste job for me to eval the template vs result experiment.

You want to have a look at DBM files. Read
perldoc DB_File
or
perldoc SDBM_File

Or you may try to install DBD::SQLite. That would give you the full
power of SQL without having to install anything but the module.

"Premature optimization is the root of all evil."

How many users are we talking about? Millions? I would not sweat over
a few KB you might save.


Jenda
===== [Email Removed] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery

Well, I got it reading from a directory, Mike at the Image::Magick mailing
list help me out... "The read must contain the path as well as the filename.

$image->Read (file=> "$path\$file");"

but I am stil having some problems with Scale and Write. The error is:

"my" variable $img masks earlier declaration in same scope at C:/Program
Files/
erlEdit/scripts/image_test.pl line 25.
JPEG 70048.jpg
Can't call method "Scale" on an undefined value at C:/Program
Files/PerlEdit/sc
ipts/image_test.pl line 24.

As you can see the program starts to read from the image directoy, but when
it hits "Scale", I get the undefined value error. I'm not sure what that
means.

-------------------------------
#!/user/bin/perl -w

use strict;
use Image::Magick;

my $image_source_folder = "C:/images";
my $image_dest_folder = "C:/images_small";

opendir(IMAGES,$image_source_folder);
my @images_to_process_list=grep {!(/^./) && -f "$image_source_folder/$_"}
readdir(IMAGES);
closedir (IMAGES);

foreach my $image_source_file(@images_to_process_list) {

my $img = new Image::Magick;

my $status=$img->Read("$image_source_folder\$image_source_file");

if ($status eq "") {

my $fmt = $img->Get('format');
print "JPEG $image_source_filen";
my $img->Scale(width=>'30', height=>'30');
my
$img->Write("jpg:$image_dest_folder\$image_source_file");
undef $img;
}
}

Thanks for any help!

Brian


-----Original Message-----
From: Wiggins d'Anconia [mailto:[Email Removed]]
Sent: Thursday, September 09, 2004 6:32 PM
To: Brian Volk
Cc: Beginners (E-mail)
Subject: Re: perl crashing at $image->Read (file=> *ARGV);


Please bottom post....

Brian Volk wrote:

Either....

It appears that the docs for I::M are incorrect and that C<Read> and
C<Write> must take a filehandle. Difficult to tell since all the code
is XS/C and I didn't feel like popping the hood on it. You could try
switching back to using a handle but I would be more specific about it,
so for instance, within the foreach you would have:

open my $READHANDLE, $filename or die "Can't open file for reading: $!";
$image->Read('file' => $READHANDLE);

etc.

Or there is an issue with the installation, paths, etc. on Windows. You
should retrieve the actual error message from I::M and see what it says,
similar to,

my $result = $image->Read('file' => $filename);
print $result;

Have you checked out the info at:

http://www.dylanbeattie.net/magick/

It appears to be good info for Win32 specific stuff related to I::M.
Personally I can't even test it here so it is difficult for me to point
you in the right direction. Maybe one of the other M$ users will chime
in ...

http://danconia.org

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Yes, that's very right, I should have to do that with some db modules!!! I
am sorry I missed something to declare here . I just do it as an experiment
to know and learn how pack works in this ways.

So, I still looking for a pack way to get this job done. Actaully, I am still
quite confuse on what I can expect pack and unpack can giving help to me,
in furture. I guess I would have some light to know what pack is while this
get done.

Would you help for a little bit more ? Thanks in advise.