Re: header issues etc...
Won't multiple simultaneous requests change the our variables
unpredictably since they all have access to the symbol table?
On 7/3/07, Perrin Harkins [EMAIL PROTECTED] wrote:
On 7/3/07, Jonathan Vanasco [EMAIL PROTECTED] wrote:
i prefer storing them as class variables and using a public method to
provide access
ie:
package myfactory;
my $object= object-new();
sub get_object { return $object ;}
Using closures just makes it more confusing. Class variables are
usually implemented as globals, i.e. our $object, not my $object.
- Perrin
Re: header issues etc...
On 7/4/07, pubert na [EMAIL PROTECTED] wrote: Won't multiple simultaneous requests change the our variables unpredictably since they all have access to the symbol table? No. Every child process is completely separate and they don't share anything. Each process only handles one request at a time. And you never modify this variable after the first time the code runs anyway. - Perrin
Re: header issues etc...
On Jul 3, 2007, at 10:37 PM, Perrin Harkins wrote: Using closures just makes it more confusing. Class variables are usually implemented as globals, i.e. our $object, not my $object. agreed. i just prefer using methods locked into version numbers for a consistent api. this way the variable names can change, and the only way to get/modify vars is through the api methods. // Jonathan Vanasco | - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | CEO/Founder SyndiClick Networks | - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | Founder/CTO/CVO | FindMeOn.com - The cure for Multiple Web Personality Disorder | Web Identity Management and 3D Social Networking | - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | RoadSound.com - Tools For Bands, Stuff For Fans | Collaborative Online Management And Syndication Tools | - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Re: header issues etc...
Hi,
I jumped into the middle of this thread and it seems I am encountering a
segfault in the header just like you have described.
Could you give me an overview of your solution since I do not have your
first emails to this list.
Thanks
Tyler
pubert na wrote:
I fixed it... apparently it not like the return $self if defined
$self; ... return $class id ref $class is better form anyway...
thanks and sorry about all the emails ;)
On 7/2/07, *pubert na* [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] wrote:
I was able to narrow down the problem I was having, and produce a
test case for you folks. Below are two relatively self-explanatory
files. If I navigate to test.cgi, it will appear to load the page
properly, but if I hit the reload button a bunch of times in a
row, the error_log will log segfaults. I pasted a sample at the
bottom of this message. I'd appreciate any help at all.
Obviously the issue is coming from CGI.pm's header function, which
*should* be ok with mod_perl2. Thanks again. --Pubert
##BEGIN FILE test.cgi
#!/usr/bin/perl
use lib qw(/var/www/cgi-bin/);;
use strict;
use CGI;
use testclass;
my $cgi=new CGI;
my $tc = testclass-new({CGI=$cgi});
$tc-doit();
1;
##BEGIN FILE testclass.pm http://testclass.pm
package testclass;
my $self;
#
sub new {
#
# This is the
constructor.
my ( $class, $args ) = @_;
return $self if defined $self;
$self = {};
bless $self, $class;
$self-{CGI}=$args-{CGI};
return $self;
}
sub doit{
print $self-{CGI}-header;
print hello;
}
1;
Begin error_log snipper
[Mon Jul 02 18:45:34 2007] [notice] SIGHUP received. Attempting
to restart
[Mon Jul 02 18:45:34 2007] [notice] Digest: generating secret for
digest authentication ...
[Mon Jul 02 18:45:34 2007] [notice] Digest: done
[Mon Jul 02 18:45:34 2007] [notice] Apache/2.2.4 (Unix) DAV/2
mod_apreq2-20051231/2.6.1 mod_perl/2.0.2 Perl/v5.8.8 configured --
resuming normal operations
[Mon Jul 02 18:45:39 2007] [notice] child pid 7925 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:39 2007] [notice] child pid 7926 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:39 2007] [notice] child pid 7927 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7928 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7929 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7931 exit signal
Segmentation fault (11)
Re: header issues etc...
On 7/2/07, pubert na [EMAIL PROTECTED] wrote:
my $self;
[...]
sub doit{
print $self-{CGI}-header;
print hello;
}
This is bad. You're using a variable that you didn't pass to doit().
That means you're creating a closure. The sub will remember the $self
it saw when you first ran it, and it will never notice that $self
changes later. You need to pass $self to this sub as a parameter in
order to make this work.
- Perrin
Re: header issues etc...
[ Please keep it on the list ] On 7/3/07, pubert na [EMAIL PROTECTED] wrote: The app I'm working with uses this as a method for object b to retrieve the instance of object a, which created it. i.e. An object x, creates 4 objects, a,b,c, and d, then calls a method in object a. Object a needs a reference to object b so it calls $foo=CLASSX::getInstance() which returns $self. Object a can then call $foo-getObjectB and it has what it wants. I don't really understand this description. If you're trying to code a singleton pattern, use global variables to hold the object. That makes it clearer what your intent is. Apparently this does not work at all under mod_perl. The only fix I can think of is passing the instantiating object as a parameter when the object is created. What do you guys usually do? Scoping works the same as usual under mod_perl. If you need access to object instances, you can use a singleton pattern, storing the objects in global variables, or you can pass the instances to the sub that needs to use them. - Perrin
Re: header issues etc...
On Jul 3, 2007, at 5:51 PM, Perrin Harkins wrote:
I don't really understand this description. If you're trying to code
a singleton pattern, use global variables to hold the object. That
makes it clearer what your intent is.
Scoping works the same as usual under mod_perl. If you need access to
object instances, you can use a singleton pattern, storing the objects
in global variables, or you can pass the instances to the sub that
needs to use them.
i prefer storing them as class variables and using a public method to
provide access
ie:
package myfactory;
my $object= object-new();
sub get_object { return $object ;}
my %objects= (
'a'= object-new(),
)
sub get_object_hash { my ( $class, $flavor )= @_; return $objects
{$flavor} ;}
package myapp;
my $object= myfactory-get_object();
my $object_a= myfactory-get_object('a');
i can't remember if the $class is necessary or not. i'm responding
via my mobile :)
header issues etc...
I was able to narrow down the problem I was having, and produce a test case
for you folks. Below are two relatively self-explanatory files. If I
navigate to test.cgi, it will appear to load the page properly, but if I hit
the reload button a bunch of times in a row, the error_log will log
segfaults. I pasted a sample at the bottom of this message. I'd appreciate
any help at all. Obviously the issue is coming from CGI.pm's header
function, which *should* be ok with mod_perl2. Thanks again. --Pubert
##BEGIN FILE test.cgi
#!/usr/bin/perl
use lib qw(/var/www/cgi-bin/);;
use strict;
use CGI;
use testclass;
my $cgi=new CGI;
my $tc = testclass-new({CGI=$cgi});
$tc-doit();
1;
##BEGIN FILE testclass.pm
package testclass;
my $self;
#
sub new {
#
# This is the
constructor.
my ( $class, $args ) = @_;
return $self if defined $self;
$self = {};
bless $self, $class;
$self-{CGI}=$args-{CGI};
return $self;
}
sub doit{
print $self-{CGI}-header;
print hello;
}
1;
Begin error_log snipper
[Mon Jul 02 18:45:34 2007] [notice] SIGHUP received. Attempting to restart
[Mon Jul 02 18:45:34 2007] [notice] Digest: generating secret for digest
authentication ...
[Mon Jul 02 18:45:34 2007] [notice] Digest: done
[Mon Jul 02 18:45:34 2007] [notice] Apache/2.2.4 (Unix) DAV/2
mod_apreq2-20051231/2.6.1 mod_perl/2.0.2 Perl/v5.8.8 configured -- resuming
normal operations
[Mon Jul 02 18:45:39 2007] [notice] child pid 7925 exit signal Segmentation
fault (11)
[Mon Jul 02 18:45:39 2007] [notice] child pid 7926 exit signal Segmentation
fault (11)
[Mon Jul 02 18:45:39 2007] [notice] child pid 7927 exit signal Segmentation
fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7928 exit signal Segmentation
fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7929 exit signal Segmentation
fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7931 exit signal Segmentation
fault (11)
Re: header issues etc...
I fixed it... apparently it not like the return $self if defined $self;
... return $class id ref $class is better form anyway... thanks and sorry
about all the emails ;)
On 7/2/07, pubert na [EMAIL PROTECTED] wrote:
I was able to narrow down the problem I was having, and produce a test
case for you folks. Below are two relatively self-explanatory files. If I
navigate to test.cgi, it will appear to load the page properly, but if I
hit the reload button a bunch of times in a row, the error_log will log
segfaults. I pasted a sample at the bottom of this message. I'd appreciate
any help at all. Obviously the issue is coming from CGI.pm's header
function, which *should* be ok with mod_perl2. Thanks again. --Pubert
##BEGIN FILE test.cgi
#!/usr/bin/perl
use lib qw(/var/www/cgi-bin/);;
use strict;
use CGI;
use testclass;
my $cgi=new CGI;
my $tc = testclass-new({CGI=$cgi});
$tc-doit();
1;
##BEGIN FILE testclass.pm
package testclass;
my $self;
#
sub new {
#
# This is the
constructor.
my ( $class, $args ) = @_;
return $self if defined $self;
$self = {};
bless $self, $class;
$self-{CGI}=$args-{CGI};
return $self;
}
sub doit{
print $self-{CGI}-header;
print hello;
}
1;
Begin error_log snipper
[Mon Jul 02 18:45:34 2007] [notice] SIGHUP received. Attempting to
restart
[Mon Jul 02 18:45:34 2007] [notice] Digest: generating secret for digest
authentication ...
[Mon Jul 02 18:45:34 2007] [notice] Digest: done
[Mon Jul 02 18:45:34 2007] [notice] Apache/2.2.4 (Unix) DAV/2
mod_apreq2-20051231/2.6.1 mod_perl/2.0.2 Perl/v5.8.8 configured -- resuming
normal operations
[Mon Jul 02 18:45:39 2007] [notice] child pid 7925 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:39 2007] [notice] child pid 7926 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:39 2007] [notice] child pid 7927 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7928 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7929 exit signal
Segmentation fault (11)
[Mon Jul 02 18:45:40 2007] [notice] child pid 7931 exit signal
Segmentation fault (11)
