Re^2: Question regarding perl subroutine

[sureshsmr]

in reply to Re: Question regarding perl subroutine
in thread Question regarding perl subroutine

Hi John Davies, Thanks a lot! That was good catch. Now I am getting a different error as below:

/usr/local/bin/perl PtfSapGetSyncStg.pl
Can't call method "agent" on an undefined value at PtfSapGetSyncStg.pl
+ line 158.

Here is the code on line 158:

my $ua->agent("Mozilla/5.0");
#my $ua->agent(""); 

is the syntax for calling "agent" method ok? I am not sure what tool is on our unix server. Any suggestions ? Thanks Suresh

[afoken]

$ua is not what you think. It is undefined, probably because the code above lacks error checks. See Basic debugging checklist.

Alexander

[monsoon]

my $ua = LWP::UserAgent->new;
$ua->agent('Mozilla/5.0');

see LPW::UserAgent

[davies]

No, that syntax cannot be right. Looking at the code you posted originally, I see:

my $ua= new LWP::UserAgent;
#my $ua->agent("Mozilla/5.0");
my $ua->agent("");

You seem to be trying to use strict;, which is good (see my home node), but without understanding what it does. PerlIntro (http://perldoc.perl.org/perlintro.html#Variable-scoping) has a section on variable scoping that it might help you to understand. my creates a new instance of a variable. You may have seen examples of messages telling you that a declaration masks a previous declaration. This is telling you that you have re-initialised a variable name, which is unlikely to be what you want. I think what you want is something like:

my $ua= new LWP::UserAgent;
$ua->agent("Mozilla/5.0");

but as I don't even know what LWP is, this is a pretty wild guess. http://search.cpan.org/~gaas/libwww-perl-6.04/lib/LWP/UserAgent.pm might be another good read.

Regards,

John Davies