> explain why creating a file takes a page of options? z/OS dates to an era of bewildering diversity in storage hardware - from punch cards to mag tape to disk

> explain why creating a file takes a page of options? z/OS dates to an era of bewildering diversity in storage hardware - from punch cards to mag tape to disks with variable length sectors and built-in hardware search mechanisms. All sorts of weirdness by modern standards. Also common at the time was record-oriented files, which are accessed not byte by byte but in a more structured manner. For example records might be 80 characters at a time, corresponding to a punch card image. Record oriented files naturally lend themselves to primitive but fast databases (evolved out of records on punch cards) and that's why mainframe OSes supported them. Similarly, file systems in those days were considered significant overhead so there's provision for raw access by sector so apps can roll their own file systems if necessary. z/OS handles all these odd cases still. And all this needs to be specified in a command language that could be parsed in like 24 KB or however much RAM it was that OS/360 was originally designed to run in... As the article says "file" is technically not the z/OS term - they're data sets. That might give a hint as to just how divergent z/OS is from just about everything else. > well Linux is just as complicated. Linux has less baggage, probably. Also the "worse is better" philosophy of UNIX kept things like quasi-database services out of the OS, for the most part. For comparative purposes check out VMS; it has some of these same features like record-oriented files in a (relatively more) modern design. > I'm seeing no compelling reason for a developer to bother to learn or use z/OS. Don't worry your vision is just fine. ;)