Sorry for the delay in writing.

I still can NOT get it DONE. I got today's time and yesterday's time as well ( ie = - 86400)

perl auto_date_range.ok.pl

Mar 28 16:56:55

yesterday Mar 27 16:56:55

today Mar 28 16:56:55

Sun Mar 27 16:56:55 2016

Mon Mar 28 16:56:55 2016

Error parsing time at /usr/lib64/perl5/vendor_perl/Time/Piece.pm line 469.

#!/usr/bin/perl

use strict;
use warnings;
#use 5.010;

use Time::Piece;
#use Time::Seconds;

my $format = '%b %e %T';

my $time = Time::Piece->new;
#my $yesterday = $time - ONE_DAY;
my $yesterday = $time - 86400;

print $time->strftime('%b %e %T'),"\n"; 
#print $time->strftime('%b %e'),"\n"; 

print "yesterday\t", $yesterday->strftime('%b %e %T'),"\n";
print "today\t", $time->strftime('%b %e %T'),"\n"; 

print $yesterday,"\n";
print $time,"\n";

#print  "yesterday\t", $yesterday,"\n";
#print "today\t", $time,"\n";


##my $start = Time::Piece->strptime('Mar 27', $format);
my $start = Time::Piece->strptime('$yesterday', $format); #this DOES N
+OT work
#my $start = Time::Piece->strptime('Feb  1 10:30:00', $format);

##my $end   = Time::Piece->strptime('Mar 28', $format);
my $end   = Time::Piece->strptime('$time', $format); #this DOES NOT wo
+rk
#my $end   = Time::Piece->strptime('Feb  2 10:30:00', $format);

print  "yesterday\t", $yesterday,"\n";
print "today\t", $time,"\n";

open(FILE, "/var/log/maillog") or die "Couldn't open maillog: $!; abor
+ting";

while (<FILE>) {
    my ($timestamp) = /(^\w+\s+\d+\s+\d\d:\d\d:\d\d)/;
    my $t = Time::Piece->strptime($timestamp, $format);

    print if $t >= $start && $t <= $end;
}

close(FILE);
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Pls help me to solve this issue

my $start = Time::Piece->strptime('$yesterday', $format);
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Please read perlsyn on quotes and quote-like operators. Single quotes do not interpolate. You should use instead:

my $start = Time::Piece->strptime($yesterday, $format);
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Hi Monks, I finally suceeded in doing it. it works as expected. Script (my_script.pl) is given below.

#!/usr/bin/perl

use strict;
use warnings;
use Time::Piece;
use POSIX qw(strftime);

my $format = '%b %e %T';

my $today = time;
my $formatted_today = strftime "%b %e %T", ( localtime($today) );

my $yesterday = $today - 60 * 24 * 60;
my $formatted_yesterday = strftime "%b %e %T", ( localtime($yesterday)
+ );

#print "VAR1 TODAY $today\n";
#print "VAR2 YESTERDAY $yesterday\n";
#print "\n";

#print "formatted_TODAY $formatted_today\n";
#print "formatted_YESTERDAY $formatted_yesterday\n";
#print "\n";

my $start = Time::Piece->strptime($formatted_yesterday, $format);
my $end   = Time::Piece->strptime($formatted_today, $format);

print "VARIABLE END TODAY $end\n";
print "VARIABLE START YESTERDAY $start\n";
print "\n";

open(FILE, "/var/log/maillog") or die "Couldn't open maillog: $!; abor
+ting";

while (<FILE>) {
    my ($timestamp) = /(^\w+\s+\d+\s+\d\d:\d\d:\d\d)/;
    my $t = Time::Piece->strptime($timestamp, $format);

    print if $t >= $start && $t <= $end;
}

close(FILE);
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