The Advisory Boar

By Abhijit Menon-Sen <>

Exide warranty nightmare

Our UPS is hooked up to three Exide Powersafe EP65-12 SLA (Sealed Lead Acid) batteries. Normally, that gives us about six hours of backup time for my desktop, monitor, and a few assorted peripherals. It's not often that the mains power is off for so long (less than half a dozen times a year, I'd guess), but that capacity has proven invaluable in the past. For the last few months, however, the UPS has lasted for half an hour at most, even when the batteries were fully charged. Using a multimeter, I found that the voltage across one of the batteries fell rapidly to 10.5V just before the UPS died, while the other two remained above 12V. Since the batteries were still under warranty, I contacted the vendor to ask about having them replaced (which I have had to do in the past)

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Prejudice lurks in dark corners

In "Women in computing: first, get the problem right", ESR explains that everyone else just misunderstood the problems that keep women away from computing and other technical fields; and that although achieving equality is precluded by the difference in dispersion of the IQ curves, his insights can help to establish the large, happy female minority that is the best we can hope for in its stead.

Talking about prejudice in this context is lazy, stupid, [and] wrong, and the real reason women bail out of computing is that they have short fertile periods, and their biological instincts tell them not to waste time on the warrior-ethic ways of programming.

By these and other bold observations, ESR demonstrates the honesty and willingness to speak uncomfortable truths that are prerequisite to addressing the problem. For example:

I don't mean to deny that there is still prejudice against women lurking in dark corners of the field.

Prejudice. Lurking in dark corners. Who would have thought it?

I'll file this article away right next to his equally-insightful “Sex tips for geeks”.

A new symbol for the Indian Rupee

Having a custom symbol for the Indian Rupee apparently allows us to join an “exclusive club” of countries whose currencies have a “distinct identity”. Bah!

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ExtUtils::MakeMaker and the case of the C++ library

I have been working on an XS interface to a C++ library comprising three namespaces split across several source files. I wanted to keep and build these files in their own subdirectory, and have only my .xs file at the top level. This was surprisingly hard to do, and I used a silly hack to make it work—I built my objects as foo.oo instead of foo.o.

The problem is that ExtUtils::MM_Unix's c_o function returns a number of rules to create object files by compiling .c, .cc, and other files, but they all place the resulting object in the top-level directory. I didn't want to redefine everything in c_o, so I tried to override the .cc build rule in MY::postamble. That worked, but caused make(1) to complain about the duplicated rule.

So I picked an unused extension and created a build rule for it:

sub MY::postamble {'
%.oo: %.cc
	$(CXX) $(OPTIMIZE) $(DEFINE) $(INC) -o "$@" -c "$<"
'}

That worked perfectly. In my call to WriteMakefile(), I passed the names of the various "subdir/src/foo.oo" files in the OBJECT list. The objects were built by the rule, and EU::MM took care of linking them in. But I still wince a little when I see all the .oo files.

A simpler solution, adopted by Florian Ragwitz in Class::MOP, is to add "-o $@" to the build command in MY::const_cccmd().

Life with cpanminus is different

cpanm makes it so much easier to deal with CPAN module dependencies.

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Trip report: Okhla Bird Sanctuary, 2010-06-20

A brief midsummer bird-watching trip to Okhla in hot and humid conditions gave good views of all of Delhi's usual Bittern species.

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Art, taxes, and fashion

Seen a few days ago in the Hindu:

Mumbai: The Bombay High Court on Monday upheld fashion designer Tarun Tahiliani's case that he is an artist for the purpose of claiming exemption under the Income Tax Act.

How very well put. He's an artist for the purpose of claiming tax exemptions.

Goriganga: safe, but for how long?

Yesterday brought the heartening news that the Ministry of Environment and Forests has rejected NTPC's proposal to build the 261MW Rupsiyabagar-Khasiyabara power plant on the Gori river near Munsiari in Uttarakhand, because of the profound damage it would cause to the fragile and ecologically important area (which is to say nothing about how it would affect the people in the fifty-odd villages along the river that would dry up due to the diversion of water).

I've been following this project for a while, because I have a special interest in the area. I have visited a number of times for bird surveys (and I plan to do more work there in future), and my friends there have been tirelessly involved in local conservation efforts for many years; so I can claim to know a little about its ecology. It seems obvious to me that constructing a large dam there would be a disaster—no doubt it is obvious to NTPC as well, because they have been spreading misinformation about it from the very start.

To begin with, the environmental impact assessment prepared for them by WAPCOS (Water and Power Consultancy Services) is nonsense. To pick on just one section where I am qualified to comment, the biodiversity estimates are wildly inaccurate. Where they list fewer than a hundred species of plants and trees, a few thousand are documented from the area, many of which occur nowhere else. They mention only ten species of mammals and eight species of birds from an area whose checklist runs to about 300, and where I saw more than a hundred species in three days (and even an eight-year-old Ammu must have seen a few dozen on her first morning walk). Then they blithely conclude that the impact on wildlife would be minimal:

Disturbance to wildlife

During construction phase, large number of machinery and construction labour will have to be mobilized. The operation of various construction equipment, and blasting is likely to generate noise. These activities can lead to some disturbance to wildlife population. Likewise, siting of construction equipment, godowns, stores, labour camps, etc. can lead to adverse impacts on fauna, in the area. From the available data, the area does not have significant wildlife population. Likewise, area does not appear to be on the migratory routes of animals and therefore the construction of the project will not affect the animals.

Anyone who has visited the area and knows anything about wildlife would be able to see how ridiculous these claims are. The rest of the report follows in the same vein (for example, it talks about the advantages of importing migrant labour amounting to some 77% of the local population in terms of the "exchange of ideas and cultures between various groups of people which would not have been possible otherwise").

NTPC has also been hard at work in the area to make sure opposition to the project is ignored, downplayed, or eliminated. They have used force to intimidate people who questioned the project, bribed public officials (and admitted to doing so), and colluded with them to interfere in local Van Panchayat elections to disallow candidates who opposed the project. They have held "public hearings" when people from affected villages were not able to attend (because they were on an annual excursion to collect medicinal plants at higher altitudes), and refused to acknowledge and record critical questions at such hearings.

There are many people in the area who support the project because NTPC is bringing money and promises of development to a poor and remote area; and because they have no access to information about the environmental and social record of big dams in India to evaluate the promises, and no way to estimate the long-term costs to the area and their livelihoods to compare against the paltry compensation being offered for their lands today.

Now they might give me compensation…
That's not what I'm chasing. I was a rich man before yesterday.
Now all I have got is a cheque and a pickup truck, and
I left my farm under the freeway.
— Jethro Tull, “Farm on the Freeway

It remains to be seen if the MoEF's rejection is binding, or if the NTPC (which has already invested heavily in land acquisition and construction in the area), and the other people who stand to gain from the project at the expense of local inhabitants, will find some way to work around it.

How long can the Gori valley survive such determined opposition?

Nonsensical DoT crypto restrictions

What are the regulations governing the use of cryptography and the development of cryptographic software in India? The answer is either "there aren't any" or "nobody really knows".

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SATA errors with flaky power cable

Just for the record—a bad SATA power cable is capable of provoking intermittent errors such as the following:

ata4: exception Emask 0x10 SAct 0x0 SErr 0x4050002 action 0xe frozen
ata4: irq_stat 0x00400040, connection status changed
ata4: SError: { RecovComm PHYRdyChg CommWake DevExch }
ata4: hard resetting link
ata4: SATA link down (SStatus 0 SControl 300)
ata4: EH complete

Two chassis fans and a disk were sharing a single 4-pin molex connector from the power supply. The problem was that the pin sockets on the fan connectors were loose and misaligned, and one of them became dislodged when the disk connector was plugged in. Pushing the pins into place and reattaching the connectors solved the problem.