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Perhaps somebody up there is listening. Following on from yesterday’s post, we awoke this morning to a Bristol lightly covered with snow. After investigating the garden in detail for about half an hour, we decided it was time for a walk.

In answer to my question, it seems that Jack quite likes snow, but you have to sniff every square inch of it extremely carefully

Very seasonal weather we’ve been having lately. Unshifting clouds of fog, and frosty mornings. Myself and Jack both have been making the most of it.

All the weather forecasts predict that there is heavy snowfall on the way for this part of the country. I look forward to finding out what he’ll make of that.

Please allow me to introduce memberd!

Mac OS X is a funny kind of Unix as was its father NEXTSTEP. And it’s a still a family trend. Maybe it’s the final glimmering remnants of its once-trendy microkernel heritage, maybe it’s an attitude influenced by all the ‘networks of directory services are better than forests of flat files’ thinking behind NetInfo and Open Directory, it doesn’t really matter why. There’s a host of system daemons running away on the Macintosh of today, some quite unfamiliar to users more used to the more traditional Unixes (or Unix-alike) operating systems. Collections of daemons managing system services aren’t anything new of course, but many of these have unfamiliar names. They replicate entire UNIX subsystems with unfamiliar, perhaps unexpected solutions. It’s just like Unix yet still unlike Unix.

Some of them date all the way back to antique NeXT releases. Like lookupd, which looks things up in directories. You might be more familiar with it in it’s guise as ‘every now and then my computer stops resolving certain addresses’, necessitating a quick ‘sudo lookupd -flushcache‘ (one word, single dash, minimally intuitive). Others like configd are newer, (introduced in the transition to Mac OS, responsible for maintaing different ‘states’ of machine configurations such as the network ‘locations’ feature), or the excitingly named, but ultimately rather prosaic blued (responsible for the rather wonderful mac bluetooth implementation, but on first encountering it running I wondered if it was providing all the blue in the Aqua GUI). And then there’s the bang-up-to-the-minute, hipper than hip new Tiger-only ones. Chief amongst them the slicing, dicing, init/cron/xinetd replacement and more that is launchd.

All of these have man pages to investigate, some of them are quite configurable, and can be fun to experiment with – especially launchd. I’m not sure how long memberd has been around for, but it was new to me today, when I stumbled across it.

As I keep a loosely organised collection of jumble-sale-quality Unix boxes, I place value in keeping my login account numeric uids synchronised across various systems I use. It obeys the principle of least surprise and is useful when network file sharing, especially via NFS. I also appreciate the access control features UNIX groups can offer to multiple users. I don’t care enough about either to actually invest in some enterprise-class networked directory service, nor am I enough of a wannabe systems administrator to aspire to wrestling such a monster into seving my will. So I generally shell in ad-hoc and adjust such things on a host by host, account by account sort of basis, as the situation demands. On OS X this can mean interacting with NetInfo, but that’s okay, I’m weird enough to quite like NetInfo, I’ve known it a while.

So today I was fiddling with some group permissions, and I actually ended up making a couple of groups entirely redundant. So I removed them from NI completely. After I was done I noticed from running id, that I was still a member of a couple of them. More oddly, the system could still identify them by name. So I panicked, assuming I’d deleted a set of NetInfo keys that were in entirely the wrong dictionary. On inspecting the damage it all looked fine. Then I realised that group membership changes were one of those things that are fixed in your environment, cached by the login shell. So I logged in and out. Still no good, the phantom groups persisted. Mental alarm bells were ringing at this point, so I started doing some digging. Walking through the list of running processes and poking at man pages led me to find memberd.

It starts up at system boot and keeps running. It has a fine man page. It seems to be how OS X 10.4 resolves user group membership. More pertinently, it maintains a cache of such information. This cache can be flushed when stale by running

memberd -r

from a root shell. And that fixed my all my troubles. Well, it got rid of the sticky invalid groups anyway.

We recently spent a long weekend in a holiday cottage down in Cornwall. Jack came along too. One afternoon we took him down to the coast near Par to walk along the beach.

Previously he’d indicated that having sand underfoot was the main point about beach walks, the sea only provoking minimal investigation. He seemed quite interested in the sea this time, enough to indulge in some fairly enthusiastic paddling. Perhaps the abundance of weed and rock pools drew him in. No swimming though, he still draws the line firmly at armpit depth.

It has been eight years and several months since my last haircut. A change is as good as arrest.

See also webcam

NeXT Stop: interesting facial hair!

Sadly it didn’t work out with Charlie, I had to return him to the shelter.

He’d settled in well and improved in behaviour in almost every way, apart from one significant lingering problem. He developed a growing tendency to bite people, quite unpredictably and increasingly without offering any warning prior to the strike. It was a difficult decision to finally make, as aside from this most anti-social and hard-to-treat of dog misbehaviours he was good company, and I miss having him around the office in the day.

Jack has taken it in good spirits though. I rather get the impression that he views this as some kind of promotion.

The idea to get a second dog was inspired chiefly by Jack’s fervent enthusiasm for dog company. He’d act deflated after returning from a spell in dog hotel , and sometimes after meeting any dog pals on a walk. Rather than another pedigree, an RSPCA rescue dog this time. And something in a smaller size. Charlie immediately caught my eye on touring the Bristol dogs home.

A blend of terrier, he came with a warning. Twice rejected by adopters for aggressive or defensive behaviour. A couple of trial visits worked out well enough, so he’s now a permanent resident. He does suffer from anxiety, and has demonstrated a tendency to snap and snarl defensively when feeling threatened. Most of the time he’s fairly affectionate, although still a little stand-offish around people. He’s improving all the time, I think, as he becomes more familiar to his new home.

The pair of them have adjusted to each other’s company well, and keep each other busy throughout the day. It’s quite remarkable how much exercise they seem to offer each other. Prior to Charlie’s arrival Jack really required two or even three longish walks per day; anything less and he’d be an awkward bundle of nervous over-activity. Now the pair of them are content staging day-long Greek Wrestling contests, a single walk in the early evening suffices. It may be counter-intuitive, but in some ways it seems two dogs are more easily managed than one.

At the time we decided to buy the house, the facade was discolouring dirty-brown pebble dash. “We’ll have to paint that.” I told myself, without any real understanding of whether this was practical, or even possible. So we moved in, and the front of the house remained much as it was, bar a spot of weeding. A year passed.

A couple of weeks ago, we noticed a man up a ladder painting the exterior of a house a few doors down from us. A man with a van, and a sign suggesting painter for hire¹. Enquiries were made, a quote offered that sounded like the going rate, for all I know about it, and a date fixed for early next week. The only thing left to determine was the colour.

I felt very strongly that if one was going to the expense of paying someone to paint your front wall, then it probably ought to be something exuberant. A colour statement. Modern paint technology being what it is, exterior paints are now an array of colours quite startling in scope; you can choose from the majority of shades on the Dulux colour chart. Which we did. I favoured an extreme sunshine yellow or a bold orange, something earthy and ostentatious. The other party favoured light blue. A compromise was reached.

That’s Dulux “Royal Regatta:3″ on the base, and “Royal Regatta:6″ on the highlights. I’d link to their colour chart, but the website is a stupid java gigantic line-noise URL and dynamic effects nightmare. It works well enough to browse though, so go look if you care; not that colours over the web can be remotely accurate. I don’t think any of the paint shops expect to sell gallons of the deep base colours, after trying a couple of different branches of B&Q we had to get them to order some in, it arrived with only a day to spare.

It was mildly exciting getting it done. The weather forecast suddenly turned to week-long downpours in the middle of July right for when we had it pencilled in. Somehow we got away with it. The dogs extracted plenty of entertainment out of having a strange man on a ladder attached to the house front.

The work in progress seemed to become something of a local talking point, with people often stopping to converse with Howard the painter as they passed. A genial fellow, he explained to me that he relied on these passing conversations, along with the sign propped against his van, to bring in most of his commissions. He thought our colour choice made for a good advertisment. Even a week after he’d finished you might sometimes see passers by, suddenly suprised by the hue, stop what they were doing for a couple of beats and gawp before moving on.

¹ H. Crawford Painting Service – (0795 0089878) – painting, plastering and rendering