Re: Who clears /tmp regularly

Hello Vern,

Am 28.02.2024 um 14:27 schrieb Vern Hamberg <vhamberg@xxxxxxxxxxxxxxx>:

It seems I am mistaken, thanks for clarifying things - the references I saw were about declaring variables in Javascript, apparently.

You're most welcome. :-)

So I dug in and find there is no mention of the /var directory in the PDF about the IFS - there's a chapter called Provided directories, so we who even read that manual would not have heard of the distinctive use that Linux/Unix admins might be familiar with.

Well, PASE was meant as a run-time environment for applications being copied over from AIX. Only lately, IBM is working hard to make it something akin "Linux services for i" (to take the Windows analogy). :-)

Normal, interactive applications rarely store things which I'd expect in /var, so there's no need for it. But when we talk about a more complete system with background processes (saving their process-ID in files /var/run) or classic mail servers (storing data in /var/mail, and /var/spool), etc., the picture changes a bit.

The hybrid approach of IBM i comes with its own challenges to interlink the UNIX world as people know it with the IBM i world as most people in here know it. So I hope to occasionally help people in understanding stuff with my Linux skills, alongside with others here having experience in both worlds.

Interestingly, I did see references to /var in some links to IBM z.

Yes, the Unix Environment on OS/390 and successors is much more complete, feature-wise, when compared with PASE.

Another thought - IFS has been presented as a combination of Windows and Unix file systems, mixed in standards like POSIX - here's something from the PDF -

The integrated file system is a part of the IBM i operating system that supports stream input/output and storage management similar to personal computer and UNIX operating systems, while providing an integrating structure over all information stored on your system.

Definitely not Windows. Using / as a path separator is very much UNIX. :-) I think the reference to "personal computer" dates back to PC-DOS and file names with the same restrictions as QDLS.

But yes, the IFS provides POSIX compatibility on a low level:
- Hierarchy of directories
- No intrinsic structure of file contents, but just a stream of bytes

The Document Library System did that, too but was implemented differently, performed poor enough to make IBM manufacture the IPCS to embrace Windows (and later, Linux) and was never updated to provide more modern (long) file names.

:wq! PoC