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perldatedatetimeperl-module

Convert one format of date to another format using perl Date::Manip

I am trying to convert incoming date into another format below is the code I have written. 

#!/usr/bin/perl 
#
use POSIX qw(strftime);
use Date::Manip;
my $string = "Run started at 12:01:48 PM on Aug 19 2016 ";

my @array = split(' ',$string);

$string  = "12:01:48 PM Aug 19, 2016";

$unix_time = UnixDate( ParseDate($string), "%s" );
#print $unix_time;

my $datestring = strftime "%a %b %e %H:%M:%S %Y", gmtime($unix_time);
printf("date and time - $datestring\n");

I want the output in Fri Aug 19 12:01:48 2016 but right on PM is not getting considered can you please help me here ?

Solution

  • Have you considered using Time::Piece instead of Date::Manip? It is part of the standard Perl distribution (since Perl 5.10) and is generally considered to be far superior to Date::Manip.

    You need to use strptime() (string parse time) to convert your string to a Time::Piece object and then strftime() (string format time) to convert your object to a string in the required format.

    #!/usr/bin/perl

use strict;
use warnings;
# We use modern Perl - specifically say()
use 5.010;

use Time::Piece;

my $string = '12:01:48 PM Aug 19, 2016';

my $tp = Time::Piece->strptime($string, '%H:%M:%S %p %b %d, %Y');

say $tp->strftime('%a %b %e %H:%M:%S %Y');

    Update: And to answer your original question, I think you're getting burnt by time zones. It seems that ParseDate() assumes that the string is in the local time zone - but you're using gmtime() to generate your new date string. If you switch that to localtime() you will get the answer you want.