Readers sound off.
Sex Clarified

Seymour Cray didn't like virtual memory and has been quoted as saying: “Memory is like sex; it's better when it's real.” Whereas Paul Barry (LJ March 2002, Letters) apparently wasn't aware of Seymour's quip, Linus certainly was; his comment comparing software to sex is an obvious allusion. Perhaps it's not that Linus needs to choose his words more carefully; perhaps it's that authors should explain the literary significance of these words for the younger generation.

—Collin Park

Netfilter Rescue

After spending a few nights with LJ [see David Bandel's “Taming the Wild Netfilter” in the September 2001 issue, available at /article/4815] at hand's reach to configure my firewall, I came across the URL www.boingworld.com/workshops/linux/iptables-tutorial. This is to me the best source I have found on Netfilter. I believe the reference to Rusty Russel's document is a tribute to Rusty's own work, but the document is not usable for a basic user like me, a simple, average Linux user! Please to advertise this URL to your user if they have troubles using the wild, wild Netfilter.

—Thomas Smets

For more on Netfilter, see David Bandel's more advanced article “Netfilter 2: in the POM of Your Hands” in this issue.


GT Explained

Gary Bickford's letter in the February 2002 issue of LJ states: “GTO is an acronym (Gran Turisimo Omologato), which according to AltaVista means 'great accredited tourism', which I suspect doesn't express the flavor of the phrase.”

He's right—Gran Turisimo refers to a racing class (Grand Touring, or GT) of cars, and Omologato (“homologated” in English) refers to the particular group of cars that was built specifically to fulfill the racing organization's requirements. As it turns out, Ferrari cheated on this; they never actually built the number of cars they were supposed to, but the organization never called them on it.

Most Pontiac dealers, when asked where the GTO moniker came from, were at a loss to explain any of this when the acronym was tacked onto the 389-engined version of the Pontiac Tempest.

—David Spellman

Speedier PHP

I found a small problem when using the caching PHP file [see Bruno Pedro's “Improving the Speed of Web Scripts” in the March 2002 issue of LJ]. The md5 hash is generated by using the PHP_SELF name of the called PHP script. But what if I generate content depending on the query string? I changed from PHP_SELF to REQUEST_URI, so it generates a unique cache file per unique parameters. This way I saved 90% execution time compared to running against my MySQL data sources.

—Kai Kretschmann


In the March 2002 issue, on page 94, “'Using Mix-ins with Python', Linux Journal, April 2000” should read “'Using Mix-ins with Python', Linux Journal, April 2001”, i.e., the referenced article appeared in the April 2001 issue, not 2000.

—Chuck Esterbrook