POSIX Everywhere

Speaker: Mark Overmeer

Abstract

Although the maintainers define POSIX as "a set of standard operating system interfaces based on the Unix operating system", there is much more to POSIX. For one, large parts of the standard are available on many other platforms, even Windows. And, it is not as much as an enforcing standard: it is more like a describing standard with quite a freedom to simplify or extend the actual provided functionality. POSIX plays an important role when we attempt to write portable code. When you restrict yourself to the over 1200 described functions (in the full standard by The Open Group) you may be able to port your code between operating systems with little effort. Many programming languages wrap parts of the POSIX specification in their own "smart" thin interface. When high performance and complex system integration is needed, you need to go around that smartness. You probably need to dive into the POSIX details, reading long manual pages. During this talk, I will show how we improve POSIX support in a scripting language (Perl). How can we work around portability issues (in general)? What does the OS tell us about the features it supports? In an additional project, I build a "POSIX knowledge base" which shows exactly which OS'es (per version) support which features and system constants. While coding, you can already predict some portability problems to be expected. It also shows interesting system relations and OS history.

Biography

Mark Overmeer (markov) started with Unix in 1985, and did not leave that field since. He worked as computing center programmer at the NLR (National Aerospace Laboratories), as trainer for AT Computing, and the last 13 years as self-employed programmer and system administrator (see http://markov.solutions) Mark is a very active contributor to Perl. Besides, he is secretary of various organisations... until last year also NLUUG board member. Mark organized a number of open-themed conferences, workshops, and meetings.