Beefy Boxes and Bandwidth Generously Provided by pair Networks
P is for Practical
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
hi
to ensure 1 instance of the application running using perl
i have a suggestion
1. pls open a specific port for locking
port must be greater than 10000 and less than 60000
ex: port 28004
2. so as long as the port is open, then, meaning there is still program running on that particular port
3. upon program exit, close the port
i have an ex code below:
hope this helps
its a class
how to use??



#-----------------------------------------------------


use PortLocker();
my $port = 52480;
my $locker = new PortLocker();
if(! $locker->lock())
{
die("Port Already lock, pls check if already running!\n");

#--- failed, port already locked
}
#--- continue here your program

. #then before exit, pls unlock the port

$locker->unlock();


#-----------------------------------------------------






PortLocker.pm ( code )

#----------------------------------------------------------------------------------------------
# Filename : PortLocker.pm
# Description : this is the package that will lock a specified port#
# Date : 08-10-2001
# Ver : ver1.1
# Author : bayugyug
#----------------------------------------------------------------------------------------------



package PortLocker;
use IO::Socket;

#--- set vars here
my $portlock = undef;
use constant PORT_LOCK => 28788;


#---
$| = 1;
my $VERSION = "1.01";





sub new
{


my $type = shift;
my $self = {};
$self->{'PORT'} = $_[0];
$self->{'PORT'} = PORT_LOCK if(int($self->{'PORT'}) <= 0);
bless $self, $type;

}



sub lock()
{

my $self = shift;
my $port = $self->{'PORT'};


$portlock = new IO::Socket::INET (
LocalHost =>
'localhost',
LocalPort => $port,
Proto => 'tcp',
Listen => 1
);

$self->debug("lock() :: port ($port) ok");
#--- return ok/fail

unless( $portlock )
{
return 0;
}

return 1;
}


sub unlock()
{

my $self = shift;
if(defined($portlock))
{
close($portlock);
}

$portlock= undef;
$self->debug("unlock() :: ok");
}


#---
sub debug()
{
my $self = shift;
my (@parm) = (@_);
my $msg = join(' : ',@parm);
my $scr = "Ver$VERSION";

print "$scr - $msg\n";
}


1;


(END) #----------------------------------------------------- hope this helps, tnx #!/bin/bayugyug


In reply to Re: Ensuring only one copy of a perl script is running at a time by bayugyug
in thread Ensuring only one copy of a perl script is running at a time by eyepopslikeamosquito

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others romping around the Monastery: (7)
As of 2024-03-28 10:44 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found