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i have the problem that i am not able to get a simple perl script doing a database connection and query. here the error i get:
install_driver(ODBC) failed: Can't locate DBD/ODBC.pm in @INC (you may need to install the DBD::ODBC module) (@INC contains: /Library/Perl/5.18/darwin-thread-multi-2level /Library/Perl/5.18 /Network/Library/Perl/5.18/darwin-thread-multi-2level /Network/Library/Perl/5.18 /Library/Perl/Updates/5.18.2/darwin-thread-multi-2level /Library/Perl/Updates/5.18.2 /System/Library/Perl/5.18/darwin-thread-multi-2level /System/Library/Perl/5.18 /System/Library/Perl/Extras/5.18/darwin-thread-multi-2level /System/Library/Perl/Extras/5.18 .) at (eval 4) line 3.
Perhaps the DBD::ODBC perl module hasn't been fully installed,
or perhaps the capitalisation of 'ODBC' isn't right.
Available drivers: DBM, ExampleP, File, Gofer, Proxy, SQLite, Sponge.
at testperldb.pl line 10.
I've a script which works fine on FC20. But, when I try to execute the same script on CentOS(CentOS Linux release 7.5.1804 (Core)), it hangs. On further, investigation it was revealed that, it is not able to match the prompt given. Please note it is able to match host prompt but not application prompt. Here is a brief detail of the issue
Code of the wrapper function which is used to create object of Net::Telnet-
package api::Telnet;
use strict;
use warnings;
use Net::Telnet;
use Exporter;
use Carp;
our @ISA = qw (Exporter);
our @EXPORT = qw (
&open_pty
&close_pty
);
# Constant global variables
use constant SSH_TIMEOUT => 1800;
sub spwan_pty
{
my (@cmd) = @_;
my ($pid, $tty, $tty_fd);
# Create a new pseudo terminal
use IO::Pty ();
my $pty = new IO::Pty or die $!;
# Execute the program in another process
# Child process
unless ($pid = fork) {
die "problem spawning program: $!\n" unless defined $pid;
# Disassociate process from existing controlling terminal
use POSIX ();
POSIX::setsid
or die "setsid failed: $!";
# Associate process with new controlling terminal
$pty->make_slave_controlling_terminal;
$pty->set_raw();
$tty = $pty->slave();
$tty_fd = $tty->fileno;
close $pty;
# Make stdio use the new controlling terminal
open STDIN, "<&$tty_fd" or die $!;
open STDOUT, ">&$tty_fd" or die $!;
open STDERR, ">&STDOUT" or die $!;
close $tty;
exec @cmd
or die "problem executing $cmd[0]\n";
} # end child process
$pty;
}
sub open_pty
{
my (%args) = @_;
# Start ssh program.
my $pty = &spwan_pty("ssh",
"-l", $args{user_name},
"-e", "none",
"-F", "/dev/null",
"-o", "PreferredAuthentications=password",
"-o", "NumberOfPasswordPrompts=1",
"-o", "StrictHostKeyChecking=no",
"-o", "UserKnownHostsFile=/dev/null",
$args{ip_addr}
);
# Create a Net::Telnet object to perform I/0 on ssh's tty
my $ssh = new Net::Telnet (
-fhopen => $pty,
-prompt => $args{prompt},
-telnetmode => 0,
-cmd_remove_mode => 1,
-timeout => SSH_TIMEOUT,
-output_record_separator => "\r",
#-errmode => sub { print "Telnet FAIL\n"; }
);
# Wait for the password prompt and send password.
$ssh->waitfor(-match => '/password: ?$/i', -errmode => "return")
or die "problem connecting to \"$args{ip_addr}\": ", $ssh->las
+tline;
$ssh->print($args{user_pswd});
# Wait for the shell prompt.
my (undef, $match) = $ssh->waitfor(
-match => $ssh->prompt,
-match => '/^Permission denied/m',
-errmode => "return"
) or return $ssh->error("login failed: expected shell prompt ", "d
+oesn't match actual\n");
return $ssh->error("login failed: bad login-name or password\n") i
+f $match =~ /^Permission denied/m;
# logging
$ssh->input_log($args{log_file});
$ssh->cmd("ifconfig");
$ssh->cmd("date");
return $ssh;
}
sub close_pty
{
my ($tty) = shift;
$tty->close();
}
1;
The code successfully creates a Net::Telnet object and spawn the application, but it is unable to match the prompt of the application, due to which it hungs and the script is unable to proceed forward. Here is the log generated-
Hello, I have a file that has a hash stored in it. I am trying to read that hash as it is using eval but I am getting following error:
Global symbol "%hash1" requires explicit package name (did you forget to declare "my %hash1"?) at tiny.pl line (print Dumper(\%hash1);) 14.
Execution of tiny.pl aborted due to compilation errors.
Please help me understand the issue here, thank you
#file.pl : my %hash1 = (hello => 1,
hi =>2 );
#tiny.pl
#!/home/utils/perl5/perlbrew/perls/5.24.2-021/bin/perl
use strict;
use warnings;
use Path::Tiny qw( path );
use Data::Dumper;
my $file = 'file.pl';
open(my $fh, '<', $file) or die "Could not open file $file";
eval($fh);
close $fh;
print Dumper(\%hash1);
I want to be able to take arbitrary lines containing variables that are defined in the program, and interpolate them.
#!/usr/bin/env perl
use 5.010;
use warnings;
use strict;
my $var1 = "abel";
my $var2 = "baker";
my $var3 = "charlie";
while (my $line = <DATA>) {
chomp $line;
say "Before interpolation: $line";
say "After interpolation: " . perform_interpolation($line);
say '';
}
sub perform_interpolation {
my $text = shift;
# now what?
}
__DATA__
I'd like to see this one: $var1.
How about \$var3? You shouldn't interpolate \$var3 (but it would be ni
+ce if you'd remove the backslash)
Try a concatenation: $var1$var2
I've seen String::Interpolate mentioned in my searches, but unless I'm misunderstanding something,
I'd have to know in advance what variables I'd be interpolating
What I'm trying to do is create a program template where a comment block right after the shebang line (possibly containing
scalar variables like $program or other constants or environment variables) can be rendered to produce a usage statement.
The perform_interpolation() subroutine would be part of the template and wouldn't know specifically what variables the programmer
might want to interpolate for the usage statement.
Can String::Interpolate do this? Or is there a simpler way?
Hi Expert,
I am using the PERL language with the PostgreSQL database and in a couple of database function, we are using the plperl as language.
We are basically calling the SOAP API in the function, however yesterday we faced the issue where PARL had sent the SIGALRM signal and my database got crashed.
Can you please review and help me to resolve the issue, either by a code change or a configuration change.
CREATE OR REPLACE FUNCTION sendclaimcoversheet(
text,
text)
RETURNS integer AS
$BODY$
use strict;
use warnings;
use SOAP::Lite;
use Try::Tiny;
use Time::Piece;
my $first = $_[0];
my $second = $_[1];
try
{
my $host = `hostname`;
my $rv = spi_exec_query("select * from getsprocurl('sendclaimc
+oversheet','".$host."')");
my $url = $rv->{rows}[0]->{ret_url};
elog(NOTICE, 'Host Name ' . $host . ' URL '. $url );
my $soap = SOAP::Lite->new();
my $service = $soap->service($url);
my $response = $service->sendClaimCoversheet($first, $second
+);
return $response;
}
catch
{
my $ex = $_;
return 'SOAPFAULT: ' . localtime->strftime('%m/%d/%Y') . ' ' .
+ $ex;
}
$BODY$
LANGUAGE plperlu VOLATILE STRICT
COST 100;
ALTER FUNCTION sendclaimcoversheet(text, text)
OWNER TO postgres;
I am trying to create a Win32 application (with Strawberry Perl (v5.14.4) on Win10) displaying graphic computations. In order to optimize the process, I want to divide the management of my virtual buffer into small pieces computed by individual threads, then compile the results and copy the virtual buffer on the screen.
My problem is the combination of Win32::GUI and threads (I have also tried forkmanager without success). Threads without Win32 is ok, Win32 without threads is ok, but using both is not. Here is a simple sample code to illustrate the issue (you can enable/disable the use of Win32 with the variable $use_win or change the amount of threads with the variable $t_amount):
#!/bin/perl
use Win32::GUI();
use threads;
use strict;
use warnings;
use Data::Dumper;
my $use_win=1; # Create Win32 GUI interface (1) or not (0)
my $t_amount=4; # Amount of threads to create
my $textbox;
my $win;
my $draw;
if($use_win){
# Initialize window
$win=new Win32::GUI::Window(
-left => 0,
-top => 0,
-width => 300,
-height => 300,
-name => "Window",
-text => "Test",
);
$win->InvalidateRect(1);
$textbox=$win->AddTextfield(
-name => "Output",
-left => 5,
-top => 5,
-width => 275,
-height => 255,
-text => "");
# Start application
$draw=$win->AddTimer('draw',1000);
$win->Show();
Win32::GUI::Dialog();
}else{
draw_Timer();
}
sub Window_Terminate{-1}
sub draw_Timer{
my @threads;
my @ret;
my $c;
my $d;
# Assign range of computation to fork processes
foreach $c(1..$t_amount){
$d=$c-1;
push(@threads,threads->new(\&draw,($d*10),($d*10+10)));
}
foreach my $thread(@threads){
@ret=$thread->join;
foreach my $data(@ret){
$use_win?$textbox->Append("|".$data):print"|".$data;
}
$use_win?$textbox->Append("\n"):print"\n";
}
}
sub draw{
my $begin=shift;
my $end=shift;
my @tbl;
my $cpt;
for($cpt=$begin;$cpt<$end;$cpt++){
push(@tbl,$cpt);
}
return(@tbl);
}
So I delegate all methods that don't exist to the obj attribute. The problem is that methods like DESTROY seem to get diverted to the AUTOLOAD subroutine. Is there a better way to achieve what I want to do?
$PM = "Perl Monk's";
$MCF = "Most Clueless FriarAbbotBishopPontiffDeaconCuratePriest Vicar";
$nysus = $PM . ' ' . $MCF; Click here if you love Perl Monks
Hello,
I'm trying to make my script more efficient so I decided to learn how to use fork.
This question is more on how to write it nice and clean
I have about 13 different calls that create files. Those calls are not depended and they can run parallel:
I understand how to create a fork and how to check if there is one and why it is important to use the wait function.
But I don't know how to make it look nice, clean and readable. Should I create a special function which will be called every time I need to create X (for example 5) forks? How should I keep track of those forks? If for example, I have 13 things I can run parallel, should I use 13 forks (running on a strong machine)? Meaning how to determine how many forks to use?
I would really love to see some real example with for example 13 different calls.
