About A.P. Lawrence

A.P. Lawrence provides SCO Unix and Linux consulting services http://www.pcunix.com
Race Conditions

A “race condition” is a circumstance where you have two things that really need to happen sequentially, but don’t.

Can’t Connect to Internet
· 1

We talked about DNS problems at Fallure to resolve, but there are other reasons why a particular machine may be unable to browse the Internet while others on the same lan still can.

Slow Down, Simplify

Microsoft’s most recent updates apparently caused problems more than a few users: Microsoft Patch Snafu Grows, Users Seek Workaround.

Resistance is Futile

Microsoft says recovery from malware is becoming impossible. Well, duh.

But is it Programming?

Apple has put out a tutorial introducing programming with Core Data, Xcode and Interface Builder. Even if you’ve never written a line of code in your life – and maybe even especialy if you have not – go take a look at Building a Sample Core Data Application.

Who Said That?

My wife and I had run out for errands and had stopped at a D’Angelo sub shop. We were just about to get out of the car when the phone rang. My wife rolled her eyes but I took the call because, well, because that’s what I do. Somebody has a problem, I try to answer the phone.

Tar Wild Card Interpretation

I had this email earlier this week:

We Have the Brains

At Do sandals and ponytails really hold back Linux? former Massachusetts chief information officer Peter Quinn complains that the Linux community is unprofessional and that this is holding back more widespread adoption of Linux. I’m sure he really believes that.

OpenOSX Virtualization for OS X

OpenOSX is a port of QEMU for OS X. It’s a universal binary, so it works on the Intel Macs without translation.

Tomorrows’s Date

At How can I find tomorrow’s or yesterday’s date in a script?, some anonymous person left what I consider to be a stupid comment.

File Date Comparison

Sometimes you want to use the date of a file somewhere else. For this example, we’ll use the case where a file shouldn’t be overwritten if it was created or changed today.

Enabling Linux telnet

This has to be one of the more common support calls that I get. The telnet daemon is no longer usually installed by default, so people are surprised when their newly installed Linux system won’t answer telnets.

Lady and the Scamp (SCO does the Web)

If you visit SCO’s website (yeah, I know, why would you?) soon enough, you may see SCO’s new Scamp logo: an evil looking bulldog grinning at you across folded arms.

Unexpected entries in Apache error_log

For some time now I have noticed a large number of entries in my Apache error log.

Keep in touch (tcp keepalives etc.)

You can’t please everyone, so you got to please yourself.. (Ricky Nelson)

Compiling on Mac OS X

There are a lot of pre-compiled binaries available for Mac OS X, but sooner or later you will need to compile something from source.

Misunderstanding Security

At UNIX Security: Don’t Believe the Truth, Thom Holwerda makes a rather silly argument that Unix security is no better than the worst of Windows security because the result to the user is the same: his personal files can be damaged by a worm or virus even if system files are more protected.

Reuse or Write New?

Sometime last summer I was involved in a fairly complicated Perl project. It was one of those “Well, it’s just like the thing you did for X, but now we need it for Y and Z”.

Simple Schedule

I often get asked for web-based scheduling programs. I’ve done quite a few of them over the years, sometimes using scripts available from the web, but more often writing my own simply because I don’t like modifying other people’s code.

VMware’s Threat to Microsoft

First off, I’m not suggesting VMware is gunning for Microsoft. However, recent developments in their product line aren’t exactly favorable to Microsoft.

Mac OS X Security

Mac and Linux users aren’t used to turning on the news and hearing about security threats that affect us.

Should ‘halt’ Call ‘shutdown’?

As mentioned briefly in the comments section of Bootstrapping your Linux Machine, recent Linux systems have added a convenience feature to the ‘halt’ and ‘reboot’ commands: they actually call ‘shutdown’ if the system isn’t in init state 0 or 6.

How Shells Call Other Programs

An article about How Linux or UNIX Understand which program to run got picked up by a few dozen RSS feeds recently. It’s not a bad article.

A ps Problem with BBX

Someone recently asked me about increasing command width for ‘ps’ on SCO Unix.