my open Raspberry Pi questions

• Should I use a USB-attachable external disk for swapping? (I do have a few "spare" ones)
• …

To be continued …

AIX moans: "Cannot open or remove a file containing a running program"

• http://www.linuxmisc.com/11-unix-aix/994cba5a5792b68b.htm

I came across this phenomenon in various contexts on AIX. 

It really sounds like "text file busy" from the old Unix days.

Looks like the guys who misuse this error message for there miserable situations actually mean "cannot open or remove a file". I call this capturing.

Looks like some variants of the "copy" utility (like CPAN File::Copy) use this error message instead of "no such file or directory". Maybe this happens in concurrent environments / situations, where a file disappears between the call to File::Copy and the actual kernel "open". Once "open" has a file handle, the inode access counter gets incremented, and the file cannot really disappear any longer, as long as it remains open ie. did not get closed again.

To be continue …

wiki URL shortening with MediaWiki and Apache

https://www.mediawiki.org/wiki/Manual:Short_URL/Apache

I would really like to achieve that with my recently set up wiki, but so far to no success.

Apple just suggested, that I should update X11 on Mavericks

http://xquartz.macosforge.org/downloads/SL/XQuartz-2.7.5.dmg

I would love to do it immediately, but I guess the DMG is big and I shouldn't do it through mobile phone Internet.

running more than 1 blog from one WordPress site …

First I tried to employ WordPress on my Synology NAS for that, but that does not look trivial at the 2nd look.

• http://wordpress.org/tags/multiblog – "WordPress › Support » Tags — multiblog"
• http://wordpress.org/tags/multisite – …
• http://codex.wordpress.org/Create_A_Network – looks like a nice description of how to proceed to "create a network of sites"

Actually … – at the link(s) above they show an RSS feed link for a specific tag – maybe that's good enough for my purposes – maybe not.

My WordPress installation on my NAS:

• Before I start fiddling in the way described for multi-site WordPress installations (patching various PHP files), I am tempted to upgrade to the very latest WordPress release available.
• But of course with Synology DSM, you are a little restricted …
• …

Looks like this is not my last and successful attempt to get going with WordPress.

Facit: It works for simple purposes, but in my situation (blogging at least separately in English and in German) it's not yet for me. With blogger.com it's rather easy to have separate blogs. And if you are cautious enough, particular ones can really be considered as anonymous.

Update …:
I assume, I have more flexibility, if I install WordPress on my web space at shuttle.de rather than on my NAS. It's Debian there.

Update 2013-12-25:

• http://codex.wordpress.org/Create_A_Network
• http://codex.wordpress.org/User:Beltranrubo/BitNami_Multisite – their installer requires to be run as root, that does not work for me on the site, where I intended to make use of it

I am not sure, whether I will go for a "sub-domains" (AKA domain-based) or for "sub-directories" (AKA path-based).

I am using "sub-domains" with blogger.com so far, but certainly only because there was no other option.

I assume, "sub-directory" will cause not as much Apache fiddling. Just "jochen.hayek.name/blog-en" and "jochen.hayek.name/blog-de" and so forth to be set up (more or less) separately …

Update 2013-12-25:

• http://codex.wordpress.org/Create_A_Network
• unpack the tar.gz into subdirectory wordpress
• add the line mentioning WP_ALLOW_MULTISITE as descibed within "Create A Network"
• visit the readme.html of my wordpress subdirectory in a browser and do as described there

how to let GNU Emacs "Untabify Upon Save"?

EmacsWiki: Untabify Upon Save

There are colleagues, that don't want to see tabs in scripts sources, that I edited.

Apparently there isn't a nice switch saying, that there shouldn't be tabs in a certain file.

software design paradigm "convention over configuration" applied in software testing

Convention over configuration - Wikipedia, the free encyclopedia

I created a testing framework for one of my projects, and for quite a while I maintained the test cases in a "configuration data structure" (luckily) with rather strict conventions. Let me call that a CDS!
I listed every single test case with all its necessary details there. That was rather cumbersome and did not make me eager to introduce new test cases.
Looking at the fact, that it cost me less than 20 hours to "cast the conventions into code", makes it look rather unclear, why I had hesitated for a couple of months to do so.
Now I am able to drop any "productional data case" into my repository of test cases, and start from there with test driver. That is quiet a relief.

The difference between a raw test case taken from a production system and a (complete) test case executed by my testing framework is "reference data". My testing framework is in a way supportive resp. smart enough by helping in creating "reference data" from the corresponding test data. Certainly a human being must consider the crucial difference between test data and reference data and has to adapt the reference data accordingly.

To be continued.