# more perl_epoch
open my $in, '<', 'jabadm_history' or die "Bummer: $!";
open my $out, '>', 'jabadm.txt' or die "What: $!";

while(my $line = <$in>){
    if(my ($epoch) = $line =~ /^#\+(\d+)\s*$/){
        my $human_readable = `date -d \@$epoch`; # or:
        #     my $human_readable = scalar localtime $epoch;
        print $out $human_readable;
    }
    else{
        print $out $line;
    }
}
# ls -lrt jabadm_history
-rw-r--r-- 1 jabadm sapsys 1518 Mar 27 13:31 jabadm_history

# ./perl_epoch
./perl_epoch: line 1: open: command not found
./perl_epoch: line 2: open: command not found
./perl_epoch: line 4: syntax error near unexpected token `)'
./perl_epoch: line 4: `while(my $line = <$in>){'