this blog is girtby.net

Making Trouble

Here is a puzzle for software developers who know about the GNU make tool. Answer after the fold below.

Say we have a makefile target for a file called timestamp. As you might guess, the file contains the current time as reported by the date utility. Let’s see what happens when we try to make it:

$ ls timestamp
ls: timestamp: No such file or directory
$ make timestamp
make: `timestamp' is up to date.
$ ls timestamp
ls: timestamp: No such file or directory

Hmm. What’s going on here? Perhaps timestamp is a phony target? Maybe the debug output will be more enlightening:

$ make -dr timestamp
GNU Make 3.80
[... irrelevant output snipped ...]
Updating goal targets....
Considering target file `timestamp'.
 File `timestamp' does not exist.
 Finished prerequisites of target file `timestamp'.
Must remake target `timestamp'.
Successfully remade target file `timestamp'.
make: `timestamp' is up to date.

OK that didn’t help. So I bet you’re dying to look at the Makefile.

DATE=/bin/date

timestamp :
    ${DATE) > ${@}

You don’t need to know anything special about makefiles to solve this one. Perhaps the only non-obvious part is that the @ variable refers to “the current target”, in this case the timestamp file.

Worked it out yet?

Now You See It, Now You Dont

Jon Udell quoted an excerpt from Microsoft CTO and blogger Ray Ozzie which I thought sounded interesting. When you click the accompanying link, you are taken to the relevant post, and then immediately whisked away to another domain which is apparently the new location for Ozzie’s blog.

MacOS X Essentials

A while back I posted a list of Windows XP essentials, and promised a MacOS X equivalent. Chris’ recent purchase has finally prompted me to make good on this promise.

Unlike the windows list, most of my OS X essentials are actually part of the operating system or at least a pre-installed application. So this isn’t so much a list to remind myself what software to install when performing a from-scratch operating system install. Instead it’s more a list of apps to recommend to other MacOS X users, sorted by category. With gratuitous use of icons, stolen from the very applications themselves. Here we go.

Full Throttle OpenWRT

The secure shell (ssh) protocol is such a wonderous invention. I can’t say (really) how much I rely on this protocol to connect to various boxes scattered about the place, especially my home OpenWRT gateway. It is incredibly useful to be able to get into the home network from anywhere to fix things, copy forgotten files from a home PC, kick off lengthy operations, or just keepin’ it real and kickin’ it freestyle. Whatever that means.

Great Moments in Systems Administration, Part XXXIV

[File this one under “long and rather mundane tales of systems administration posted here for therapeautic purposes only”.]

Web 2.0 Release Notes Missing

I would like to announce that as of today I am changing my name to alastr in order to be fully Web 2.0-compliant.

Positive Signs

While I have been trying to decide lately whether Beazley and his ALP homiez are as totally adrift and clueless as ruthlessly described by Mark Latham, or merely snookered by far more wily political opponents, my attention has been drawn to the conservative side of politics. In addition to the usual nonsense there have been some very positive signs of late.

iTunes Library Preening

Preening one’s iTunes library is one of those continually rewarding pastimes. Adding cover art, fixing up meta-data, adding playlists, it’s all endless fun. iTunes has a particularly entertaining feature where each track in your library can be given a rating, from one to five stars. This is a great way of instantly locating the best-of-the-best tracks in your collection. If you’re like me you preen your ratings constantly.

Journey to the Center of Ethics

This week has had a couple of amusing stories in the media which have caught my eye. The first was the brilliant tree impersonation by Telstra COO Phil Burgess.

Educational Dilemma Resolved

Many years ago I went to The Kings School.