sub exec_safe {
    my ($command, $timeout, $nice_val) = @_;
    my @return_val;
    eval {
        local $SIG{ALRM} = sub { die "Timeout\n" };
        alarm $timeout;
        @return_val= `nice -n $nice_val $command`;
        alarm 0;
    };
    if($@) { # If command fails, return non-zero and msg
        die unless $@ eq "Timeout\n";   # propagate unexpected errors
        return ("Command timeout",1);
    } else {
        chomp @return_val; push(@return_val, $? >> 8);
        return @return_val;
    }
}