[28857] in Perl-Users-Digest
Perl-Users Digest, Issue: 101 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Feb 9 21:51:50 2007
Date: Fri, 9 Feb 2007 18:50:23 -0800 (PST)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Fri, 9 Feb 2007 Volume: 11 Number: 101
Today's topics:
Re: 'use lib' question <nan.li.g@gmail.com>
Re: :) <tadmc@augustmail.com>
a, b, - and c? <g_m@remove-comcast.net>
Re: a, b, - and c? <spamtrap@dot-app.org>
Re: a, b, - and c? <sisyphus1@nomail.afraid.com>
Re: a, b, - and c? <g_m@remove-comcast.net>
Apache/mod_perl server getting stuck <ignoramus799@NOSPAM.799.invalid>
Re: Apache/mod_perl server getting stuck <ignoramus8098@NOSPAM.8098.invalid>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: 5 Feb 2007 06:37:15 -0800
From: "nan li" <nan.li.g@gmail.com>
Subject: Re: 'use lib' question
Message-Id: <1170686235.911526.69230@v45g2000cwv.googlegroups.com>
On Feb 2, 5:05 pm, John Bokma <j...@castleamber.com> wrote:
> "nan li" <nan.l...@gmail.com> wrote:
> > On Feb 2, 4:00 pm, "Paul Lalli" <mri...@gmail.com> wrote:
> >> On Feb 2, 3:35 pm, "nan li" <nan.l...@gmail.com> wrote:
>
> [..]
>
> >> > Use of uninitialized value in string at t11.pl line 5.
> >> > Empty compile time value given to use lib at t11.pl line 5
> >> > t11.pl syntax OK
>
> [..]
>
> >> use lib $ENV{XYZ};
>
> >> Paul Lalli
>
> > But if I use this, I still get the warning:
>
> No, no, you get a different one.
>
> > Empty compile time value given to use lib at t11.pl line 7
>
> Maybe because XYZ is empty...
>
> --
> John Experienced Perl programmer:http://castleamber.com/
>
> Perl help, tutorials, and examples:http://johnbokma.com/perl/
You are right. I didn't set XYZ :-( Thanks a lot.
------------------------------
Date: Sat, 3 Feb 2007 09:14:39 -0600
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: :)
Message-Id: <slrnes99mv.t1e.tadmc@tadmc30.august.net>
john.swilting <john.swilting@wanadoo.fr> wrote:
>:)
Please do not drop litter in the newsgroup.
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: Sat, 3 Feb 2007 05:07:04 -0500
From: "~greg" <g_m@remove-comcast.net>
Subject: a, b, - and c?
Message-Id: <Kuidnb1VyqBDw1nYnZ2dnUVZ_sapnZ2d@comcast.com>
Why does this work...
use strict;
$|=1;
sub Test
{
(*a,*b) = @_;
print "$a\n$b\n";
}
my $A = 'this is';
my $B = 'a test';
Test(\$A,\$B);
(prints:
this is
a test)
...but this doesn't?
use strict;
$|=1;
sub Test
{
(*a,*c) = @_;
print "$a\n$c\n";
}
my $A = 'this is';
my $C = 'a test';
Test(\$A,\$C);
(Variable "$c" is not imported at ... line...
Global symbol "$c" requires explicit package name at ... line ...)
?
(Something to do with 'sort()' maybe?)
------------------------------
Date: Sat, 03 Feb 2007 05:23:56 -0500
From: Sherm Pendley <spamtrap@dot-app.org>
Subject: Re: a, b, - and c?
Message-Id: <m2ireja69v.fsf@Sherm-Pendleys-Computer.local>
"~greg" <g_m@remove-comcast.net> writes:
> Why does this work...
... undeclared $a & $b ...
> ...but this doesn't?
... undeclared $a & $c ...
> (Something to do with 'sort()' maybe?)
Yes, exactly. From "perldoc strict", with regard to "use strict 'vars';":
Because of their special use by sort(), the variables $a and $b are
exempted from this check.
sherm--
--
Web Hosting by West Virginians, for West Virginians: http://wv-www.net
Cocoa programming in Perl: http://camelbones.sourceforge.net
------------------------------
Date: Sat, 3 Feb 2007 21:22:46 +1100
From: "Sisyphus" <sisyphus1@nomail.afraid.com>
Subject: Re: a, b, - and c?
Message-Id: <45c462f3$0$9770$afc38c87@news.optusnet.com.au>
"~greg" <g_m@remove-comcast.net> wrote in message
news:Kuidnb1VyqBDw1nYnZ2dnUVZ_sapnZ2d@comcast.com...
> Why does this work...
> use strict;
> $|=1;
> sub Test
> {
> (*a,*b) = @_;
> print "$a\n$b\n";
> }
> my $A = 'this is';
> my $B = 'a test';
> Test(\$A,\$B);
> (prints:
> this is
> a test)
>
> ...but this doesn't?
> use strict;
> $|=1;
> sub Test
> {
> (*a,*c) = @_;
> print "$a\n$c\n";
> }
> my $A = 'this is';
> my $C = 'a test';
> Test(\$A,\$C);
> (Variable "$c" is not imported at ... line...
> Global symbol "$c" requires explicit package name at ... line ...)
>
> ?
>
> (Something to do with 'sort()' maybe?)
>
Yep - in that $a and $b are special (as you probably know).
So, as soon as you name the variable(s) something other than 'a' or 'b', you
need to take extra steps.
This does the right thing:
use strict;
use warnings;
$|=1;
sub Test
{
our ($x, $y);
(*x,*y) = @_;
print "$x\n$y\n";
}
my $A = 'this is';
my $C = 'a test';
Test(\$A,\$C);
Cheers,
Rob
------------------------------
Date: Sat, 3 Feb 2007 05:58:44 -0500
From: "~greg" <g_m@remove-comcast.net>
Subject: Re: a, b, - and c?
Message-Id: <ebCdneiAWM1-91nYnZ2dnUVZ_sWdnZ2d@comcast.com>
very satisfying! :)
thanks, all
~greg
------------------------------
Date: Tue, 06 Feb 2007 15:38:50 -0600
From: Ignoramus799 <ignoramus799@NOSPAM.799.invalid>
Subject: Apache/mod_perl server getting stuck
Message-Id: <P6KdnQfB4KD3aFXYnZ2dnUVZ_tunnZ2d@giganews.com>
Lately, in the last week or so, my Apache server with mod_perl began
to get stuck.
How can I find out where (in mod_perl code) am I stuck, can I maybe
send some signal to apache and get a dump of current state of its
subprocesses, including state of mod_perl code.
Thanks
i
------------------------------
Date: Fri, 09 Feb 2007 06:53:54 -0600
From: Ignoramus8098 <ignoramus8098@NOSPAM.8098.invalid>
Subject: Re: Apache/mod_perl server getting stuck
Message-Id: <Iu-dnZ-hEqh_81HYnZ2dnUVZ_sHinZ2d@giganews.com>
I found the solution, it is here:
http://perl.apache.org/docs/1.0/guide/debug.html
Using the Perl Trace
To see where an httpd is "spinning", try adding this to your script or
a startup file:
use Carp ();
$SIG{'USR2'} = sub {
Carp::confess("caught SIGUSR2!");
};
The above code assigns a signal handler for the USR2 signal. This
signal has been chosen because it's least likely to be used by the
other parts of the server.
We check the registered signal handlers with help of
Apache::Status. What we see at http://localhost/perl-status?sig is :
USR2 = \&MyStartUp::__ANON__
MyStartUp is the name of the package I've used in mine startup.pl.
After applying this server configuration, let's use this simple code
example, where sleep(10000) will emulate a hanging process:
debug/perl_trace.pl
-------------------
$|=1;
print "Content-type:text/plain\r\n\r\n";
print "[$$] Going to sleep\n";
hanging_sub();
sub hanging_sub {sleep 10000;}
We execute the above script as
http://localhost/perl/debug/perl_trace.pl, we have used $|=1; and
printed the PID with $$ to learn what process ID we want to work with.
No we issue the command line, using the PID we have just saw being
printed to the browser's window:
% kill -USR2 PID
And watch this showing up at the error_log file:
caught SIGUSR2!
at /home/httpd/perl/startup/startup.pl line 32
MyStartUp::__ANON__('USR2') called
at /home/httpd/perl/debug/perl_trace.pl line 5
Apache::ROOT::perl::debug::perl_trace_2epl::hanging_sub() called
at /home/httpd/perl/debug/perl_trace.pl line 4
Apache::ROOT::perl::debug::perl_trace_2epl::handler('Apache=SCALAR(0x8309d08)')
called
at /usr/lib/perl5/site_perl/5.005/i386-linux/Apache/Registry.pm
line 140
eval {...} called
at /usr/lib/perl5/site_perl/5.005/i386-linux/Apache/Registry.pm
line 140
Apache::Registry::handler('Apache=SCALAR(0x8309d08)') called
at PerlHandler subroutine `Apache::Registry::handler' line 0
eval {...} called
at PerlHandler subroutine `Apache::Registry::handler' line 0
We can clearly see that the process "hangs" in the code executed at
line 5 of the /home/httpd/perl/debug/perl_trace.pl script, and it was
called by the hanging_sub() routine defined at line 4.
On Tue, 06 Feb 2007 15:38:50 -0600, Ignoramus799 <ignoramus799@NOSPAM.799.invalid> wrote:
> Lately, in the last week or so, my Apache server with mod_perl began
> to get stuck.
>
> How can I find out where (in mod_perl code) am I stuck, can I maybe
> send some signal to apache and get a dump of current state of its
> subprocesses, including state of mod_perl code.
>
> Thanks
>
> i
------------------------------
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 V11 Issue 101
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