Have a look at Log::Log4perl. It provides the PID functionality you want, besides being a powerful log framework: 
 
#!/usr/bin/perl

use strict;
use warnings;

use Log::Dispatch::FileRotate;
use Log::Log4perl;

my $conf = qq(
  log4perl.category.Pid          = INFO, ScreenAppender, PidFileRotate
+Appender

  log4perl.appender.ScreenAppender         = Log::Log4perl::Appender::
+Screen
  log4perl.appender.ScreenAppender.stderr  = 0
  log4perl.appender.ScreenAppender.layout  = PatternLayout
  log4perl.appender.ScreenAppender.layout.ConversionPattern=[%P] %p %d
+ %F:%L %m%n
  log4perl.appender.ScreenAppender.Threshold  = DEBUG

  log4perl.appender.PidFileRotateAppender           = Log::Dispatch::F
+ileRotate
  log4perl.appender.PidFileRotateAppender.filename  = pid.$$.log
  log4perl.appender.PidFileRotateAppender.mode      = append
  log4perl.appender.PidFileRotateAppender.size      = 10000
  log4perl.appender.PidFileRotateAppender.max       = 5
  log4perl.appender.PidFileRotateAppender.layout    = PatternLayout
  log4perl.appender.PidFileRotateAppender.layout.ConversionPattern=[%P
+] %p %d %F:%L %m%n
);
Log::Log4perl::init( \$conf );
my $log = Log::Log4perl::->get_logger(q(Pid));

# log messages of various severity
$log->debug(qq{Hey hey my my}) if $log->is_debug();
$log->info(qq{Hey hey my my}) if $log->is_info();
$log->warn(qq{Hey hey my my}) if $log->is_warn();
$log->error(qq{Hey hey my my}) if $log->is_error();
$log->fatal(qq{Hey hey my my}) if $log->is_fatal();

# die with a log message
$log->logdie(qq{Hey hey my my});

[download]
Writes both to screen (STDOUT) and a file named pid.pid.log that is rotated on 50K: 
[4548] INFO 2006/11/30 07:36:31 586445.pl:30 Hey hey my my
[4548] WARN 2006/11/30 07:36:31 586445.pl:31 Hey hey my my
[4548] ERROR 2006/11/30 07:36:31 586445.pl:32 Hey hey my my
[4548] FATAL 2006/11/30 07:36:31 586445.pl:33 Hey hey my my
[4548] FATAL 2006/11/30 07:36:31 586445.pl:35 Hey hey my my

[download]
Andreas
--

In reply to Re: Find the PID of current program by andreas1234567
in thread Find the PID of current program by Anonymous Monk

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