Ian F. Darwin has worked in the computer industry for three decades: with Unix since 1980, Java since 1995, and OpenBSD since 1998. He wrote the freeware file(1) command used on Linux and BSD and is the author of Checking C Programs with Lint, Java Cookbook, and over seventy articles and several courses (both university and commercial) on C and Unix. In addition to programming and consulting, Ian teaches Unix, C, and Java for Learning Tree International, one of the world's largest technical training companies. He runs BSD UNIX (OpenBSD and/or OS X) on all of his computers; the only Windows he has are made of glass and look out over the countryside north of Toronto.