Most of the effort in the software business goes into the maintenance of code that already exists.

Defect-free software does not exist.

I was going to visit IBM for six months as a visiting scientist. Now, six months is a lot of time, so I came with a whole list of projects that I might want to work on.

I don't expect an overnight change of all desktops to what the US Military used to call B3 level security. And even that would not stop users from shooting themselves into the foot.

However, writing software without defects is not sufficient. In my experience, it is at least as difficult to write software that is safe - that is, software that behaves reasonably under adverse conditions.

I want to avoid locking people into solutions that work only with Postfix. People should have a choice in what software they want to use with Postfix, be it anti-virus or otherwise.

Qmail out of the box works fine, so people will want to use it regardless of licensing restrictions, even when the software does not ship with their system software.

When I write software, I know that it will fail, either due to my own mistake, or due to some other cause.

The challenge with Postfix, or with any piece of software, is to update software without introducing problems.

Sure, but competition is good for the user.

As of today, the Postfix mail transport agent has almost 50,000 lines of code, comments not included.

Like all software, Qmail can survive only when it keeps up with changing requirements.

Most of the effort in the software business goes into the maintenance of code that already exists.

Coming back to the topic of computer security, the TCP Wrapper is an example of such a safety net. I wrote it when my systems were under attack by someone who appeared to walk through walls.

This will surprise some of your readers, but my primary interest is not with computer security. I am primarily interested in writing software that works as intended.

For many people my software is something that you install and forget. I like to keep it that way.

At the time the Sendmail program had a very poor reputation with respect to security, with four root vulnerabilities per year for two successive years.

One bug in an SMTP server can open up the whole machine for intrusion.

Windows favors multi-threading, which means that a service is implemented by one single process.

Writing software that's safe even in the presence of bugs makes the challenge even more interesting.

Postfix keeps running even if one Postfix process dies; Windows requires that someone restarts the service.

Lack of documentation is becoming a problem for acceptance.

The Postfix security model is based on keeping software simple and stupid.

In a previous life I wrote the software that controlled my physics experiments. That software had to deal with all kinds of possible failures in equipment. That is probably where I learned to rely on multiple safety nets inside and around my systems.

My reply is: the software has no known bugs, therefore it has not been updated.

Adding functionality is not just a matter of adding code.

Natural resources are so vast that no single individual or business is going to protect them; they don't have an incentive to.

The bronze powder business, however, no longer required my personal attention, and was well managed by those I had chosen as the guardians of a secret, which was long and honourably kept.

I have done things politically, and I've been running a business at the same time, but I sort of joke that to some extent I do more than most legislators have done in their whole careers, and I've been doing it as a part-time job.

Howard Hughes himself was a regular at the restaurant, and in a way it became his headquarters, too. Howard had recently relocated to Las Vegas, so when he wanted to do business in Los Angeles, he went into the back of our restaurant to use the telephone.

Prosperous farmers mean more employment, more prosperity for the workers and the business men of every industrial area in the whole country.

My parents were amazing people who had no business being together - and they knew it.

We mean by "politics" the people's business - the most important business there is.

Slovakia's joining the OECD in 1999 is totally dependent on meeting economic reforms required such as transparency and legislation that permits fair and open conduct of trade and business.

The way the business things work in Russia is you have to meet people, you have to go through a certain amount of etiquette and business things are done just simply by a shake of the hand and whether they like you or not.

I make no claim to being a business genius. You can make so much money in this business that it loses its value.

It costs a great deal of money to do a musical, and the more money involved, the more big business influences the artform.

It's a very hard and competitive business in which you have to fight every day in order to impose yourself.

I know the history of the record business so well because I followed Billie Holiday into the record studios. It was so primitive compared to the sophisticated business today.

Chicago kept industry, attracted new business, became the center for convention trade and transportation.

I have been, and will go on, fighting that damnable, dirty, rotten business with all the power at my command.

All business success rests on something labeled a sale, which at least momentarily weds company and customer.

I knew an actor's career goes up and down and back up again. Your standing in this business can't be your whole identity; otherwise, you're doomed.

The surest way to return to the people's business is to listen to the people themselves: We need to drop this whole scheme of federally controlled health care, start over, and work together on real reforms at the state level that will contain costs and won't leave America trillions of dollars deeper in debt.

Again, I say I will be glad to tell what songs I have ever sung, because singing is my business.

You have to be a star to be in this business.

The government must do all it can to help reduce interest rates for business.

Do what you love to do and give it your very best. Whether it's business or baseball, or the theater, or any field. If you don't love what you're doing and you can't give it your best, get out of it. Life is too short. You'll be an old man before you know it.

I have never had anything done. I've been asked if I had breast implants. Whether I did or not, it's nobody's business but my own.