AT&T Co is presenting a series of three European software developer conferences on Unix System V Release 4: the first was in Frankfurt, the second is here in London on April 25 and 26, and the roadshow winds up in Paris on May 9 and 10: the sessions include technical documentation on migration paths from SunOS, Berkeley and Xenix systems, and will look at other 4.0 features such as Open Look, networking, and the applications binary interface.