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Continual-Process-0.2.1
River stage zero No dependents
/ Continual::Process

NAME

Continual::Process - (re)start dead process

SYNOPSIS


            

              
              
use Continual::Process;
use Continual::Process::Loop;
my $loop = Continual::Process::Loop->new(
    instances => [
        Continual::Process->new(
            name => 'job1',
            code => sub {
                my $pid = fork;
                if ($pid) {
                    return $pid;
                }
                say "Hello world";
                sleep 5;
                say "Bye, bye world";
                exit 1;
            },
            instances => 4,
        )->create_instance(),
        Continual::Process->new(
            name => 'job2',
            code => sub {
                my $pid = fork;
                if ($pid) {
                    return $pid;
                }
                exec 'perl -ne "sleep 1"';
                exit 1;
            },
        )->create_instance(),
    ]
);
$loop->run();

DESCRIPTION

Continual::Process with Continual::Process::Loop is a way how to run a process forever.

Continual::Process creates Continual::Process::Instance which runs in a loop and if it dies, it starts again.

The code for starting a process is OS-agnostic. The only condition is that the code must return PID of the new process.

loop

Continual::Process supports more loops:

Continual::Process::Loop::Simple - simple while/sleep loop
Continual::Process::Loop::AnyEvent - AnyEvent support
Continual::Process::Loop::Mojo - Mojo::IOLoop support

METHODS

new(%attributes)

%attributes

name

name of process (only for identification)

code

CodeRef which start new process and returned PID of new process

code-sub must return PID of the new process or die!

for example Linux and fork:


            

              
              
code => sub {
    if (my $pid  = fork) {
        return $pid;
    }
    ...
    exit 1;
}

or Windows and Win32::Process


            

              
              
code => sub {
    my ($instance) = @_;
    Win32::Process::Create(
        $ProcessObj,
        "C:\\winnt\\system32\\notepad.exe",
        "notepad temp.txt",
        0,
        NORMAL_PRIORITY_CLASS,
        "."
    ) || die "Process ".$instance->name." start fail: ".$^E;
    return $ProcessObj->GetProcessID();
}

best way is use Continual::Process::Helper prepare_fork or prepare_run method

instances

count of running instances

default 1

create_instance()

create and return list of Continual::Process::Instance

LICENSE

Copyright (C) Avast Software.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

Jan Seidl <seidl@avast.com>