OSX sidebar orphans annoyance / binary XML whinge

February 21, 2010

I have circled around the Mac-Sun-Windows-Linux loop since the 1980s. Currently I am part of what Keith N calls the “invasion of the Mac brain snatchers”. Mac market share is slowly increasing amongst the general populace, but amongst astronomers its probably already the majority. If the gods that reside at One Infinite Loop have noticed this phenomenon, they maybe assume its because we appreciate and understand the power, flexibility, and beauty of OSX. Well Steve, it aint bad, but actually ITS THE UNIX. If Gnome and KDE keep improving, and Apple keep being commercial control freaks, it could be Ubuntu for me next time. (Unless there are Android laptops or something by then of course.) I just spotted  a worrying development on OSX – binary XML. Begin digression …

The OSX interface is pretty good, and the terminal interface is v.useful. (I use iTerm in preference to the standard Terminal – this is because it has tabs you can rename.) But there are some occasional annoyances. One that has hit me a few times is the issue of sidebar orphans.  You can drag aliases for frequently used folders and other items to a sidebar in the Finder, which is nice. Occasionally, as I re-organise my folders I end up with aliases for items that no longer exist, and I can’t even remove them, as when you click on the alias, you just get a message that says “can’t find this volume” or similar. I am a tad confused, as I have been trying to produce these orphans deliberately in the last few minutes and failing – moving and deleting folders seems to work ok. I just know it happens sometimes, and I have been getting a slowly longer list of them ! (I found a forum discussion here, but its a bit out of date.)

So I thought, this list has to be stored somewhere. I will find the file and edit it . Sure enough, there is a file called “com.apple.sidebar.plist” in Users/name/Library/Preferences. If I click on this file, it opens up in the Property List Editor. This has a mixture of the obvious and the gobbledygook, but its not hard to locate the item concerned and do “Delete Item”.

But its a tad mysterious. Finder says that this plist is an XML file, but it aint text; it seem to be a binary file, and the Property List Editor unpacks and formats it, as well as acting as a dedicated editor. If you try the Help menu, although it says “Property List Editor Help” it jumps straight to Xcode Help, way above my head. I isn’t a developer. I installed Xcode because I wanted Macports, which requires the X11 SDK, which comes bundled with Xcode.I just did what the nice folks at Macports told me too. I think the Property List Editor comes with Xcode, so in fact without this I would not have been able to edit this list at all.  Apparently you can change items on the command line with the “defaults” utility, or use the “plutil” utility for converting back to text – see this forum page.

This brought home to me that OSX is not just a GUI written in Unix. The OS itself, and the developer framework,  are also highly specialised constructs. Its maybe a lucky accident for us that the Unix layer is still visible and useable so that we can write shell scripts, install IRAF or whatever. This short wikipedia article explains the evolution of plist files. The original NeXTSTEP version was plain text. OSX 10.0 changed this to an XML format, defined by a public DTD; OSX 10.2 changed this to binary XML, which a normal user can’t inspect at all, and a geeky user can only inspect afer installing the Apple Developer Tools package (aka Xcode).

And there was me thinking that the point of XML was that it was an open plain text format, and that the Mac, being based on Unix, was transparent, modular, and flexible, in beautiful contrast to the incomprehensible gargantuan tangle that is the Windows Registry.  Well in relative terms, it still is.. but its a worrying trend.

For those of you who don’t want to install Xcode, there are some lightweight third party plist editors listed in the above wikipedia article, and the web page for this one also has a nice rant about binary XML.

Oh, and because I am a responsible parent, I should say “Before Using the Property List Editor, do a Back Up“, and could you all sign the disclaimer firm please ?


Emmets at Sunset

February 17, 2010

I have been using UKIRT for about a quarter of a century. Two things have changed. The first is that it works much better. UKIRT was always ground breaking and world leading, but now it is a kind of flawless machine as well. The second change is that the mountain is now heaving with tourists. Enterprising companies charge grockles two hundred bucks a shot for which they get a boneshaking ride, a nice warm coat, and the chance to shoot photos from the roof of the world. So we have to lock the door or folks wander in and bugger the dark runs.

My last night on this run saw a particularly large infestation. It was President’s Day so I guess there were lots of locals as well vacationers from Pittsburgh. (Can you imagine a holiday called “Prime Minister’s Day”?).  They were crawling all over the summit as twilight fell, and I remembered what they call tourists in Cornwall : Emmets. Cornish for ants.

Jack, Jack, and I were outside taking our own pix, and a few emmets were brave enough to speak to us. They turned out to be Welsh and were tickled to find out Jack was too. TSS Jack Ehle (not Welsh) invited them in and gave them a quick tour before they had to scuttle back to their emmet bus. They went away beaming. Well hell the government PAYS us to come here, so we should give something back to the peepul.

Lots more data. Happy days.

The sounds of youth

February 13, 2010

I do miss the Mellotron. It was the sound of my youth. I resumed my acquaintance on a flight from the UK to Hawaii for my latest observing run by listening to ancient King Crimson. With those synthesised strings a band could sound radical and modern and gushingly sentimental at the same time.

I was expecting more gushing sentiment in Hawaii. I am here to push on with UKIDSS, our infra-red sky survey, which will take a thousand nights at fourteen thousand feet. Except that now it might not finish … as UKIRT‘s closing date has been set by STFC as Dec 31st this year. So this might be my last ever UKIRT run…

So I was expecting the local staff to be wallowing in gloom, bitterness, and weepy nostalgia. What I found was a kind of resigned pragmatism. Senior staff are putting on their salesman hats and looking for buyers; junior staff are just getting on with their jobs.  And of course they are all brushing off their CVs. But there was no ranting or choking back tears.

I did get my nostalgia fix tonight though. Tom Geballe, who is currently on a staff astronomer run at Gemini, dropped in to UKIRT with his son and other visitors. Tom used to work at UKIRT many moons ago, and was touched to find CGS4 still bolted on to its Cassegrain station. He patted it gently. His son too found his head thrown back in time. The sound of his youth, he said, was the CGS4 closed cycle coolers.

But now the future is upon us ! VISTA works. See lovely new Orion picture. Last night I looked at the Orion nebula with my binoculars. Its nice to be reminded every now and again that what we do is real. It ain’t just a TV game.

Phil Charles suspended

February 2, 2010

Maybe STFC ain’t so closed and autocratic after all. I have just been hearing distressing news about Phil Charles, currently Director of SAAO, but of course very well known to UK astronomers from his long distinguished career in Oxford, La Palma, Southampton and elsewhere. Phil has been suspended for talking to his fellow astronomers about the plans of the parent body of SAAO and SALT, the South African National Research Foundation (NRF). There is a hearing due in a few days and he may well be dismissed.

You can read about the affair in a report in the Cape Times, and in a piece by an opposition politician. Its quite hard to tell exactly whats going on, because everybody in an official position is being tight lipped. But judging by the unattributed comments referred to in those articles, it seems to be connected with NRF’s bid to host the SKA, the siting of its operational centre, and the lack of consultation with SAAO staff about these issues.If anybody knows better, and can speak without breaching confidence, do let us know.

Everybody who knows Phil knows what a straightforward chap he is, and how passionate he is about South African astronomy (as well as astronomy in general !) It seems that the NRF may be concerned about controlled handling of the SKA situation, and goodness knows this will be increasingingly politically tense; but if they want to seem like responsible and competent corporate partners, then firing such a respected and trusted senior astronomer seems a pretty dim thing to do. Lets hope they see sense.

Does anybody know whether lobbying will help ? And if so, how it should be done ?

You might also want to read about pigeons are faster than email if you want to contact SAAO.