I just want print out the task.name and task.modifiedtime from $msl variable , what are the possible ways in perl ?

I assume "modifiedtime" is a typo and you really meant "lastmodifiedtime". One way is to use regular expressions to capture just the info you desire:

use strict;
use warnings;

my $msl = '
task.start
# task.id: 1
task.name:"abc"
task.info: xyz
task.schedule: 
task.notify:
task.nextruntime:
task.lastmodifiedtime: 2010-04-12T11:57:56+01:00 by user1@server1
';

my ($name) = $msl =~ /task\.name:(.*)/;
print "$name\n";

my ($time) = $msl =~ /task\.lastmodifiedtime:(.*)/;
print "$time\n";

__END__
"abc"
 2010-04-12T11:57:56+01:00 by user1@server1
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