Re: apache::registry + use strict curiosity
Yes, exactly. After the first run, $test got an entry in the symbol
table. Not usually an issue in CGI perl. =)
[EMAIL PROTECTED] (Eric Kolve) wrote:
I found something a bit curious that I was wondering if someone could
explain. I have the following apache::registry script I called test.reg:
#!/usr/bin/perl
use strict;
if($test){
# do stuff
}
print qq|HTTP/1.1 200 OK\r\n|;
print HELLO WORLD\n\n;
I ran my server in single-user mode (httpd -X) and requested the page
which causes an internal server error because I didn't declare '$test'.
I next commented out the three conditional lines:
#if($test){
# do stuff
#}
Then requested the page a second time, which executed just fine. I
uncommented those three lines and requested the page a third time, which
strangely enough actually works. Registry stats pages to see if they
change and recompiles pages I believe. So I am wondering why isn't an
exception raised on the third request about not declaring '$test'? Did
the first request put '$test' in the symbol table?
------
Ken Williams Last Bastion of Euclidity
[EMAIL PROTECTED]The Math Forum
Re: apache::registry + use strict curiosity
that's no apache::registry. that's perl
there are big guns here who can answer
your questions but it am not one of them.
On Thu, Apr 26, 2001 at 02:25:17PM -0700, Eric Kolve wrote:
I found something a bit curious that I was wondering if someone could
explain. I have the following apache::registry script I called test.reg:
#!/usr/bin/perl
use strict;
if($test){
# do stuff
}
print qq|HTTP/1.1 200 OK\r\n|;
print HELLO WORLD\n\n;
I ran my server in single-user mode (httpd -X) and requested the page
which causes an internal server error because I didn't declare '$test'.
I next commented out the three conditional lines:
#if($test){
# do stuff
#}
Then requested the page a second time, which executed just fine. I
uncommented those three lines and requested the page a third time, which
strangely enough actually works. Registry stats pages to see if they
change and recompiles pages I believe. So I am wondering why isn't an
exception raised on the third request about not declaring '$test'? Did
the first request put '$test' in the symbol table?
thanks,
--eric
Re: Apache::Registry() and strict
On Sun, 12 Nov 2000, Stas Bekman wrote: Hi, Please explain, the guide appears to recommend -w as a useful diagnostic technique (and the "Command Line Switches (-w, -T, etc)" section says -w works). The guide is correct. -w in the shebang line is equal to 'local $^W=1' for the file scope. and it does have an effect (for the file it's defined in). Stas is right, I mixed up -w and -T:-((( Sorry for bothering you guys... Bye, remco /--\ | Remco Schaar | | e-mail: [EMAIL PROTECTED] | \--/ South Park meets Linux: - "Oh my God, they killed init!" - "You bastards!"
Re: Apache::Registry() and strict
On Tue, 7 Nov 2000, Paul DuBois wrote: At 10:25 AM +0100 11/7/00, [EMAIL PROTECTED] wrote: On Tue, 7 Nov 2000, Ron Rademaker wrote: Hi, You would think so, however every doc I read (including the one you pointed out to me) told me that perl gives me a warning: Variable $foo will not stay shared at I do use -w so I should get that warning, but I don't. The variable stays defined, but it doesn't have the value of the old variable, it just passes the defined($foo) test but the value has changed to an empty array (from a full array). -w has no effect, read the guide again and use PerlWarn On :-) Please explain, the guide appears to recommend -w as a useful diagnostic technique (and the "Command Line Switches (-w, -T, etc)" section says -w works). The guide is correct. -w in the shebang line is equal to 'local $^W=1' for the file scope. and it does have an effect (for the file it's defined in). Bye, remco /--\ | Remco Schaar | | e-mail: [EMAIL PROTECTED] | \--/ South Park meets Linux: - "Oh my God, they killed init!" - "You bastards!" _ Stas Bekman JAm_pH -- Just Another mod_perl Hacker http://stason.org/ mod_perl Guide http://perl.apache.org/guide mailto:[EMAIL PROTECTED] http://apachetoday.com http://jazzvalley.com http://singlesheaven.com http://perlmonth.com perl.org apache.org
Re: Apache::Registry() and strict
Ron, This is a greivous FAQ. Please read the guide at http://perl.apache.org/guide You'll find much more than this question answered. Ed Ron Rademaker wrote: Hello, I'm just starting with mod_perl and I'm using Apache::Registry(). The second line after #!/usr/bin/perl -w is use strict; But somehow variables I use in the script are still defined if I execute the script again, in one of the script I said undef $foo at the end, but I don't think this is the way it should be done, but it did work. Anyone knows what could be causing this?? Ron Rademaker PS. Please CC to me because I'm not subscribed to this mailinglist
Re: Apache::Registry() and strict
You would think so, however every doc I read (including the one you pointed out to me) told me that perl gives me a warning: Variable $foo will not stay shared at I do use -w so I should get that warning, but I don't. The variable stays defined, but it doesn't have the value of the old variable, it just passes the defined($foo) test but the value has changed to an empty array (from a full array). Ron On Mon, 6 Nov 2000, ed phillips wrote: Ron, This is a greivous FAQ. Please read the guide at http://perl.apache.org/guide You'll find much more than this question answered. Ed Ron Rademaker wrote: Hello, I'm just starting with mod_perl and I'm using Apache::Registry(). The second line after #!/usr/bin/perl -w is use strict; But somehow variables I use in the script are still defined if I execute the script again, in one of the script I said undef $foo at the end, but I don't think this is the way it should be done, but it did work. Anyone knows what could be causing this?? Ron Rademaker PS. Please CC to me because I'm not subscribed to this mailinglist
Re: Apache::Registry() and strict
On Tue, 7 Nov 2000, Ron Rademaker wrote: Hi, You would think so, however every doc I read (including the one you pointed out to me) told me that perl gives me a warning: Variable $foo will not stay shared at I do use -w so I should get that warning, but I don't. The variable stays defined, but it doesn't have the value of the old variable, it just passes the defined($foo) test but the value has changed to an empty array (from a full array). -w has no effect, read the guide again and use PerlWarn On :-) Bye, remco /--\ | Remco Schaar | | e-mail: [EMAIL PROTECTED] | \--/ South Park meets Linux: - "Oh my God, they killed init!" - "You bastards!"
Re: Apache::Registry() and strict
Just tried, it didn't give me any useful information, I always got any other warning without PerlWarn on, so I don't think it made any difference. Anyway, even with PerlWarn on, the error.log still shows exactly the same output, everything goes well for a while, but then suddenly my defined($foo) check succeeds where it should have failed, but the old value is gone. Ron On Tue, 7 Nov 2000 [EMAIL PROTECTED] wrote: On Tue, 7 Nov 2000, Ron Rademaker wrote: Hi, You would think so, however every doc I read (including the one you pointed out to me) told me that perl gives me a warning: Variable $foo will not stay shared at I do use -w so I should get that warning, but I don't. The variable stays defined, but it doesn't have the value of the old variable, it just passes the defined($foo) test but the value has changed to an empty array (from a full array). -w has no effect, read the guide again and use PerlWarn On :-) Bye, remco /--\ | Remco Schaar | | e-mail: [EMAIL PROTECTED] | \--/ South Park meets Linux: - "Oh my God, they killed init!" - "You bastards!"
Re: Apache::Registry() and strict
Are you running with httpd -X ? What you describe sounds like it "stops working" when it hits a child for the second time. As advised, all this is described in the guide. You might want to start here: http://perl.apache.org/guide/porting.html#Exposing_Apache_Registry_secret HTH, Simon. From Ron Rademaker [EMAIL PROTECTED] Date 7 November 2000 To [EMAIL PROTECTED] Time 09:42 Copy to[EMAIL PROTECTED] (bcc: Simon Wilcox/BASE/WilliamsLea) Bcc Simon Wilcox/BASE/WilliamsLea Fax to Subject Re: Apache::Registry() and strict Just tried, it didn't give me any useful information, I always got any other warning without PerlWarn on, so I don't think it made any difference. Anyway, even with PerlWarn on, the error.log still shows exactly the same output, everything goes well for a while, but then suddenly my defined($foo) check succeeds where it should have failed, but the old value is gone. Ron __ This email contains proprietary information some or all of which may be legally privileged. It is for the intended recipient only. If an addressing or transmission error has misdirected this email, please notify the author by replying to this email. If you are not the intended recipient you must not use, disclose, distribute, copy, print, or reply on this email.
Re: Apache::Registry() and strict
Hi there, On Tue, 7 Nov 2000, Ron Rademaker wrote: Just tried, it didn't give me any useful information,... Try 'httpd -X'. 73, Ged.
Re: Apache::Registry() and strict
I just read that part of the guide, for the third time today, but still I didn't see anything that could help, I don't get any warnings and I'm not using globals. The problem does occur when trying to use a child more then once. So when I tried running with httpd -X I got the wrong output the second time. Ron On Tue, 7 Nov 2000 [EMAIL PROTECTED] wrote: Are you running with httpd -X ? What you describe sounds like it "stops working" when it hits a child for the second time. As advised, all this is described in the guide. You might want to start here: http://perl.apache.org/guide/porting.html#Exposing_Apache_Registry_secret HTH, Simon. From Ron Rademaker [EMAIL PROTECTED] Date 7 November 2000 To [EMAIL PROTECTED] Time 09:42 Copy to[EMAIL PROTECTED] (bcc: Simon Wilcox/BASE/WilliamsLea) Bcc Simon Wilcox/BASE/WilliamsLea Fax to Subject Re: Apache::Registry() and strict Just tried, it didn't give me any useful information, I always got any other warning without PerlWarn on, so I don't think it made any difference. Anyway, even with PerlWarn on, the error.log still shows exactly the same output, everything goes well for a while, but then suddenly my defined($foo) check succeeds where it should have failed, but the old value is gone. Ron __ This email contains proprietary information some or all of which may be legally privileged. It is for the intended recipient only. If an addressing or transmission error has misdirected this email, please notify the author by replying to this email. If you are not the intended recipient you must not use, disclose, distribute, copy, print, or reply on this email.
Re: Apache::Registry() and strict
Then it is definitely variable persistence ! If you really can't track down the bug, you might try posting your code to the list. Perhaps someone will spot something you've missed ? Simon. From Ron Rademaker [EMAIL PROTECTED] Date 7 November 2000 To Simon Wilcox/BASE/WilliamsLea@WilliamsLea Time 10:04 Copy to[EMAIL PROTECTED] Bcc Fax to Subject Re: Apache::Registry() and strict I just read that part of the guide, for the third time today, but still I didn't see anything that could help, I don't get any warnings and I'm not using globals. The problem does occur when trying to use a child more then once. So when I tried running with httpd -X I got the wrong output the second time. Ron __ This email contains proprietary information some or all of which may be legally privileged. It is for the intended recipient only. If an addressing or transmission error has misdirected this email, please notify the author by replying to this email. If you are not the intended recipient you must not use, disclose, distribute, copy, print, or reply on this email.
Re: Apache::Registry() and strict
Okay, here's the part where it's going wrong:
my @fields; # The variable that's causing the trouble, should be
undefined after this declaration
my $printedfields = 0;
foreach my $hash_ref (@$data_ref)
{
if (!defined(@fields)) # Passes the second time the child gets a
request, but @fields = ()
{
@fields = @$hash_ref;
}
else
{
print "tr";
if (!$printedfields)
{
$printedfields = 1;
foreach my $field (@fields)
{
print "th$$hash_ref{$field}/th";
}
print "/tr";
}
else
{
foreach my $found (@fields)
{
print "td align='center'";
my $tempfound = $found;
my $unitskey = $tempfound . "units";
my $printed = 0;
if (defined($$hash_ref{$unitskey}))
{
print "$$hash_ref{$unitskey}$$hash_ref{$found}";
$printed = 1;
}
$tempfound =~ s/min//;
$tempfound =~ s/max//;
$unitskey = $tempfound . "units";
if (defined($$hash_ref{$unitskey}) !$printed)
{
print "$$hash_ref{$found} $$hash_ref{$unitskey}";
}
elsif(!$printed)
{
print "$$hash_ref{$found}";
}
print "/td";
}
print "/tr";
print "tr/trtr/trtrtd
colspan='$#fields'$$hash_ref{productlongdescription}/td/tr" if
(($url_ref eq "") (defined($$hash_ref{productlongdescription}))
($specdb eq ""));
print "trtd colspan='$#fields' align='center'a
href='/cgi-bin/order.cgi?productcode=$$hash_ref{productcode}number=1'Bestel
dit product/a/td/tr"; # Second run causes a use of unititialised
value here, will be solved if defined checks does what is should
}
}
}
On Tue, 7 Nov 2000 [EMAIL PROTECTED] wrote:
Then it is definitely variable persistence !
If you really can't track down the bug, you might try posting your code to
the list.
Perhaps someone will spot something you've missed ?
Simon.
From Ron Rademaker [EMAIL PROTECTED]
Date 7 November 2000
To
Simon Wilcox/BASE/WilliamsLea@WilliamsLea Time 10:04
Copy to[EMAIL PROTECTED]
Bcc
Fax to
Subject Re: Apache::Registry() and strict
I just read that part of the guide, for the third time today, but still I
didn't see anything that could help, I don't get any warnings and I'm not
using globals. The problem does occur when trying to use a child more then
once. So when I tried running with httpd -X I got the wrong output the
second time.
Ron
__
This email contains proprietary information some or all of which may be
legally privileged. It is for the intended recipient only. If an addressing
or transmission error has misdirected this email, please notify the author by
replying to this email. If you are not the intended recipient you must not
use, disclose, distribute, copy, print, or reply on this email.
Re: Apache::Registry() and strict
It looks like you are trying to determine if an array is empty, in that case
replace
if (!defined(@fields))
with
if (!scalar(@fields)).
- Original Message -
From: Ron Rademaker [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Sent: Tuesday, November 07, 2000 5:26 AM
Subject: Re: Apache::Registry() and strict
Okay, here's the part where it's going wrong:
my @fields; # The variable that's causing the trouble, should be
undefined after this declaration
my $printedfields = 0;
foreach my $hash_ref (@$data_ref)
{
if (!defined(@fields)) # Passes the second time the child gets a
request, but @fields = ()
{
@fields = @$hash_ref;
}
else
{
print "tr";
if (!$printedfields)
{
$printedfields = 1;
foreach my $field (@fields)
{
print "th$$hash_ref{$field}/th";
}
print "/tr";
}
else
{
foreach my $found (@fields)
{
print "td align='center'";
my $tempfound = $found;
my $unitskey = $tempfound . "units";
my $printed = 0;
if (defined($$hash_ref{$unitskey}))
{
print "$$hash_ref{$unitskey}$$hash_ref{$found}";
$printed = 1;
}
$tempfound =~ s/min//;
$tempfound =~ s/max//;
$unitskey = $tempfound . "units";
if (defined($$hash_ref{$unitskey}) !$printed)
{
print "$$hash_ref{$found} $$hash_ref{$unitskey}";
}
elsif(!$printed)
{
print "$$hash_ref{$found}";
}
print "/td";
}
print "/tr";
print "tr/trtr/trtrtd
colspan='$#fields'$$hash_ref{productlongdescription}/td/tr" if
(($url_ref eq "") (defined($$hash_ref{productlongdescription}))
($specdb eq ""));
print "trtd colspan='$#fields' align='center'a
href='/cgi-bin/order.cgi?productcode=$$hash_ref{productcode}number=1'Beste
l
dit product/a/td/tr"; # Second run causes a use of unititialised
value here, will be solved if defined checks does what is should
}
}
}
On Tue, 7 Nov 2000 [EMAIL PROTECTED] wrote:
Then it is definitely variable persistence !
If you really can't track down the bug, you might try posting your
code to
the list.
Perhaps someone will spot something you've missed ?
Simon.
From Ron Rademaker
[EMAIL PROTECTED]
Date 7 November 2000
To
Simon Wilcox/BASE/WilliamsLea@WilliamsLea Time 10:04
Copy to[EMAIL PROTECTED]
Bcc
Fax to
Subject Re: Apache::Registry() and strict
I just read that part of the guide, for the third time today, but still
I
didn't see anything that could help, I don't get any warnings and I'm
not
using globals. The problem does occur when trying to use a child more
then
once. So when I tried running with httpd -X I got the wrong output the
second time.
Ron
__
This email contains proprietary information some or all of which may
be
legally privileged. It is for the intended recipient only. If an
addressing
or transmission error has misdirected this email, please notify the
author by
replying to this email. If you are not the intended recipient you
must not
use, disclose, distribute, copy, print, or reply on this email.
Re: Apache::Registry() and strict
I'm not quite looking for a workaround, I already got one, I'd like to
know why it's going wrong.
Ron
On Sun, 7 Nov 1999, lporcano wrote:
It looks like you are trying to determine if an array is empty, in that case
replace
if (!defined(@fields))
with
if (!scalar(@fields)).
- Original Message -
From: Ron Rademaker [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Sent: Tuesday, November 07, 2000 5:26 AM
Subject: Re: Apache::Registry() and strict
Okay, here's the part where it's going wrong:
my @fields; # The variable that's causing the trouble, should be
undefined after this declaration
my $printedfields = 0;
foreach my $hash_ref (@$data_ref)
{
if (!defined(@fields)) # Passes the second time the child gets a
request, but @fields = ()
{
@fields = @$hash_ref;
}
else
{
print "tr";
if (!$printedfields)
{
$printedfields = 1;
foreach my $field (@fields)
{
print "th$$hash_ref{$field}/th";
}
print "/tr";
}
else
{
foreach my $found (@fields)
{
print "td align='center'";
my $tempfound = $found;
my $unitskey = $tempfound . "units";
my $printed = 0;
if (defined($$hash_ref{$unitskey}))
{
print "$$hash_ref{$unitskey}$$hash_ref{$found}";
$printed = 1;
}
$tempfound =~ s/min//;
$tempfound =~ s/max//;
$unitskey = $tempfound . "units";
if (defined($$hash_ref{$unitskey}) !$printed)
{
print "$$hash_ref{$found} $$hash_ref{$unitskey}";
}
elsif(!$printed)
{
print "$$hash_ref{$found}";
}
print "/td";
}
print "/tr";
print "tr/trtr/trtrtd
colspan='$#fields'$$hash_ref{productlongdescription}/td/tr" if
(($url_ref eq "") (defined($$hash_ref{productlongdescription}))
($specdb eq ""));
print "trtd colspan='$#fields' align='center'a
href='/cgi-bin/order.cgi?productcode=$$hash_ref{productcode}number=1'Beste
l
dit product/a/td/tr"; # Second run causes a use of unititialised
value here, will be solved if defined checks does what is should
}
}
}
On Tue, 7 Nov 2000 [EMAIL PROTECTED] wrote:
Then it is definitely variable persistence !
If you really can't track down the bug, you might try posting your
code to
the list.
Perhaps someone will spot something you've missed ?
Simon.
From Ron Rademaker
[EMAIL PROTECTED]
Date 7 November 2000
To
Simon Wilcox/BASE/WilliamsLea@WilliamsLea Time 10:04
Copy to[EMAIL PROTECTED]
Bcc
Fax to
Subject Re: Apache::Registry() and strict
I just read that part of the guide, for the third time today, but still
I
didn't see anything that could help, I don't get any warnings and I'm
not
using globals. The problem does occur when trying to use a child more
then
once. So when I tried running with httpd -X I got the wrong output the
second time.
Ron
__
This email contains proprietary information some or all of which may
be
legally privileged. It is for the intended recipient only. If an
addressing
or transmission error has misdirected this email, please notify the
author by
replying to this email. If you are not the intended recipient you
must not
use, disclose, distribute, copy, print, or reply on this email.
Re: Apache::Registry() and strict
I'm not quite looking for a workaround, I already got one, I'd like to know why it's going wrong. From the perlfunc page: defined - Returns a Boolean value telling whether EXPR has a value other than the undefined value undef. [...] On the other hand, use of defined() upon aggregates (hashes and arrays) is not guaranteed to produce intuitive results, and should probably be avoided. Len
RE: Apache::Registry() and strict
from the camel book: "Use of defined on aggregates (hashes and arrays) is
deprecated."
so, change
if (!defined @fields)
to
unless (@fields)
and not only be idiomatic, but exhibit the behavior you want :)
but seriously, it's a perl thing, not a mod_perl thing:
#!/usr/bin/perl
sub test {
my @array;
if (!defined @array) {
print "not defined\n";
} else {
print "defined\n";
}
push @array, "item";
}
test();
test();
results:
not defined
defined
HTH
--Geoff
-Original Message-
From: Ron Rademaker [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, November 07, 2000 7:44 AM
To: lporcano
Cc: [EMAIL PROTECTED]
Subject: Re: Apache::Registry() and strict
I'm not quite looking for a workaround, I already got one, I'd like to
know why it's going wrong.
Ron
On Sun, 7 Nov 1999, lporcano wrote:
It looks like you are trying to determine if an array is
empty, in that case
replace
if (!defined(@fields))
with
if (!scalar(@fields)).
- Original Message -
From: Ron Rademaker [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Sent: Tuesday, November 07, 2000 5:26 AM
Subject: Re: Apache::Registry() and strict
Okay, here's the part where it's going wrong:
my @fields; # The variable that's causing the
trouble, should be
undefined after this declaration
my $printedfields = 0;
foreach my $hash_ref (@$data_ref)
{
if (!defined(@fields)) # Passes the second time the child gets a
request, but @fields = ()
{
@fields = @$hash_ref;
}
[snip]
RE: Apache::Registry() and strict
Okay, thanks (everyone).
On Tue, 7 Nov 2000, Geoffrey Young wrote:
from the camel book: "Use of defined on aggregates (hashes and arrays) is
deprecated."
so, change
if (!defined @fields)
to
unless (@fields)
and not only be idiomatic, but exhibit the behavior you want :)
but seriously, it's a perl thing, not a mod_perl thing:
#!/usr/bin/perl
sub test {
my @array;
if (!defined @array) {
print "not defined\n";
} else {
print "defined\n";
}
push @array, "item";
}
test();
test();
results:
not defined
defined
HTH
--Geoff
-Original Message-
From: Ron Rademaker [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, November 07, 2000 7:44 AM
To: lporcano
Cc: [EMAIL PROTECTED]
Subject: Re: Apache::Registry() and strict
I'm not quite looking for a workaround, I already got one, I'd like to
know why it's going wrong.
Ron
On Sun, 7 Nov 1999, lporcano wrote:
It looks like you are trying to determine if an array is
empty, in that case
replace
if (!defined(@fields))
with
if (!scalar(@fields)).
- Original Message -
From: Ron Rademaker [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Sent: Tuesday, November 07, 2000 5:26 AM
Subject: Re: Apache::Registry() and strict
Okay, here's the part where it's going wrong:
my @fields; # The variable that's causing the
trouble, should be
undefined after this declaration
my $printedfields = 0;
foreach my $hash_ref (@$data_ref)
{
if (!defined(@fields)) # Passes the second time the child gets a
request, but @fields = ()
{
@fields = @$hash_ref;
}
[snip]
Re: Apache::Registry() and strict
At 10:25 AM +0100 11/7/00, [EMAIL PROTECTED] wrote: On Tue, 7 Nov 2000, Ron Rademaker wrote: Hi, You would think so, however every doc I read (including the one you pointed out to me) told me that perl gives me a warning: Variable $foo will not stay shared at I do use -w so I should get that warning, but I don't. The variable stays defined, but it doesn't have the value of the old variable, it just passes the defined($foo) test but the value has changed to an empty array (from a full array). -w has no effect, read the guide again and use PerlWarn On :-) Please explain, the guide appears to recommend -w as a useful diagnostic technique (and the "Command Line Switches (-w, -T, etc)" section says -w works). Bye, remco /--\ | Remco Schaar | | e-mail: [EMAIL PROTECTED] | \--/ South Park meets Linux: - "Oh my God, they killed init!" - "You bastards!"
