Thanks a lot for my missing comment.

On openbsd system, typed the command:

SD_OCC1# openssl x509 -in /etc/isakmpd/certs/local.crt -noout -dates (enter!)

notBefore=Nov 23 22:31:12 2019 GMT

notAfter=Mar 19 06:52:23 2020 GMT

At thie point, I hope to change the GMT to current my contry time zone(KST).

Thanks in advance,

And followings are code changed by your recommendation.

my %MONTH_NAMES = ( "Jan" => '01',  "Feb"=> '02',  "Mar" => '03', "Apr
+"=> '04',"May" => '05',  "Jun" => '06', "Jul" => '07', "Aug" => '08',
+  "Sep" => '09', "Oct" => '10', "Nov" => '11', "Dec" => '12' );
[download]

 if(m/notBefore/) {
   chomp; ($notB1, $notB2) = split('=', $_);
   $notB2 =~ tr/:/ /;
   my($mon,$mday,$hour,$minute,$sec,$year)=split(/ /,$notB2);
   #print $mon, $mday, $hour, $minute, $sec, $year;
   $time_1 = timelocal($sec,$minute,$hour,$mday,$MONTH_NAMES{$mon},$ye
+ar);
   print $MONTH_NAMES{$mon};
 }
[download]

2020-01-09 Athanasius fixed long code line.

And followings are code changed by your recommendation.

Not really, you're still using timelocal instead of timegm_modern (and the month numbers are still off by one).

As I said, for best results, use DateTime. For the other solutions, if your local system isn't set to the right time zone, you could try forcing it via local $ENV{TZ}='Asia/Seoul';, but that's not guaranteed to work and may not be portable.

use warnings;
use strict;

my $date = "Nov 23 22:31:12 2019 GMT";
print "Input date: $date\n";

{
    use Time::Local qw/timegm_modern/;
    my %MONTH_NAMES = ( Jan=>0, Feb=>1, Mar=>2, Apr=>3, May=>4,
        Jun=>5, Jul=>6, Aug=>7, Sep=>8, Oct=>9, Nov=>10, Dec=>11 );
    my ($mon,$mday,$hour,$minute,$sec,$year) = split /\s+|:/, $date;
    my $tm = timegm_modern($sec,$minute,$hour,$mday,
        $MONTH_NAMES{$mon},$year);
    print "timegm+gmtime: ", gmtime($tm)." GMT\n";
    print "timegm+localtime: ", localtime($tm)." Local\n";
}
# - OR -
{
    use Time::Piece;
    my $tm = Time::Piece->strptime($date, '%b %d %H:%M:%S %Y %Z');
    print "Time::Piece: ", $tm->strftime, "\n";
    print "Time::Piece+localtime: ", localtime($tm->epoch)." Local\n";
}
# - OR -
{
    use DateTime;
    use DateTime::Format::Strptime;
    my $strp = DateTime::Format::Strptime->new(
        pattern => '%b %d %H:%M:%S %Y %Z', on_error => 'croak');
    my $dt = $strp->parse_datetime($date);
    print "DateTime: ",$dt->strftime("%Y-%m-%dT%H:%M:%S%z (%Z)"),"\n";
    $dt->set_time_zone('Asia/Seoul');
    print "DateTime: ",$dt->strftime("%Y-%m-%dT%H:%M:%S%z (%Z)"),"\n";
}
[download]

Hi, Haukex

Thanks a lot for your very kindly answer

I tried to execute the script but got the following error message.

It looked there were not the module in my perl version.

I am sorry to say whether there is another way to solve in my perl version?

Thanks in advance,

sd_loader# perl ./test1.pl

"timegm_modern" is not exported by the Time::Local module

Can't continue after import errors at ./test1.pl line 8

BEGIN failed--compilation aborted at ./test1.pl line 8.

sd_loader# perl ./test1.pl

Can't locate Time/Piece.pm in @INC (@INC contains: /usr/libdata/perl5/i386-openbsd/5.8.8 /usr/local/libdata/perl5/i386-openbsd/5.8.8 /usr/libdata/perl5 /usr/local/libdata/perl5 /usr/local/libdata/perl5/site_perl/i386-openbsd /usr/libdata/perl5/site_perl/i386-openbsd /usr/local/libdata/perl5/site_perl /usr/libdata/perl5/site_perl /usr/local/lib/perl5/site_perl .) at ./test1.pl line 9.

BEGIN failed--compilation aborted at ./test1.pl line 9.

sd_loader# perl ./test1.pl

Can't locate DateTime.pm in @INC (@INC contains: /usr/libdata/perl5/i386-openbsd/5.8.8 /usr/local/libdata/perl5/i386-

openbsd/5.8.8 /usr/libdata/perl5 /usr/local/libdata/perl5 /usr/local/libdata/perl5/site_perl/i386-

openbsd /usr/libdata/perl5/site_perl/i386-openbsd /usr/local/libdata/perl5/site_perl /usr/libdata/perl5/site_perl /usr/local/lib/perl5/site_perl .) at ./test1.pl line 9.

BEGIN failed--compilation aborted at ./test1.pl line 9.