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Comment Some experience... (Score 2) 375

I've recovered hundreds of floppies over the years. Here's what I've done to good effect.

(1) Find a machine with a floppy drive. If this machine hasn't had its floppy used in a while, either read/write a bunch of disks, or get it cleaned/aligned. I've opted for the former with good effect, but drives are getting old enough now that the former may be increasingly necessary. For older 5.25" drives, I'd definitely try to clean the heads, but be sure to do research so you don't grind the heads away by using the wrong methods. The reason I use the read/write method of a few disks that are new is that it gives you a chance to see if the drive is working on disks that don't matter. It might also allow you to have a minor cleaning effect from this to remove oxides from accumulated sitting time, but I'm unsure if that's what's going on. I have used different drives when the first tests failed, but never paid to have the broken drives fixed. There's just too many surplus floppy drives around. It might also help to have multiple drives.

(2) I have used both ddrecover and rescuedisk. The former is a gnu thing, the latter is included with FreeBSD. Both will incrementally read the disk and optionally write out data about what's been read. Both programs try to read as much data as possible in large blocks, then switch to smaller size reads for the damaged areas to try to get as much data off as quickly as possible with as few read-head passes. Having said that, often times there's a few stubborn sectors that just need to be tried a lot. For ddrecover, you may need to crank up the retry count to 1000 or more. rescuedisk does this automatically. I've had several disks that people have sworn are totally unreadable that I've been able to recover and placed in my hand to do something with. I've been able to recover most of them by retrying between 100 and 1000 times. When that fails, and it has in maybe 2 or 3 of the hundreds of disks I've done, I've taken the log files about what had been recovered to a different machine with a different drive and tried to read the (usually 1-4) missing sectors there. This hasn't failed me yet for disks that are hard to read merely because they are "old." My experience has been more concentrated on the 3.5" floppies than the older 5.25" floppies too. Different rules may apply there.

I guess I should caveat the above advice with "for disks that are just old". Disks that have been damaged over the years, or have had magnets run over them, etc all bets are off short of "extreme" options that might not even work.

Many of these techniques also work for reading damaged audio CDs, DVDs, etc.

Comment Re:K&R C (Score 2) 624

for (i = 0; i++; i 10)

is semantically the same as

for (i = 0; ++i; i 10)

period.

This has what K&R has brought us. Of course, the reason for this preference is that PDP-11 had postincrement addressing mode as well as pre-decrement. So you'll see more --foo than foo-- in old time code. For simple ints like the above, of course it doesn't matter one wit. But for looks like:

while (*src++ = *dst++) ;

you get much better code on a pdp-11 than the nearly similar:

*src = *dst;
while (*++src = *++dst);

because the former's data movement is just two instructions, while the latter can be up to 6. Then again, this loop kinda disproves the usefulness of the ++foo that the parent to this reply expounded. There's really nothing more "logical" about it. it isn't until you find yourself in C++ land that you might think that (since operator ++ overloading is a lot easier with preincrement rather than post increment).

So there you have it. The main reason for foo++'s prevalence in K&R is due to the historical accidents of PDP-11 addressing modes and stack growing direction.

Comment Wrong metric (Score 1) 511

Since grades are supposed to be approximately normally distributed, no technology should raise grades. They should remain the same: approximately normally distributed. The real metric would be "can Johnny read better" or "can Jenny do math better" not "are their grades higher?"

Oh, wait, forgot about that stupid grade inflation thing where we're making the tests easier and not changing the grading curve to match...

Comment Re:Pure Arrogance (Score 1) 495

This is pure arrogance. You aren't *THAT* good. Code is more than inputs and outputs. You should be judged on how you do it. It has been my near universal experience in the last 30 years of reading/reviewing code that the people most opposed to code reviews tend to be the producers of the worst, hardest to maintain code in the tree.

Comment Re:The trouble... (Score 1) 179

WinCE based boot loaders have existed for the past 10-12 years. But there's a problem with them. You can't replace the code at the reset vectors which is necessary to get the deep sleep modes working properly. You can run Linux or BSD on the box, but you'll not be able to suspend the laptop, nor will you be able to easily script the booting. If you are relying on WinCE to do the booting, you're also not able to reclaim that space in the Flash memory either.

Comment Re:This might be useful (Score 2, Informative) 179

Back in the day, the reason that the MobilePro 780 (and friends) had severe limitations running Linux/BSD was due to the design of the hardware. WinCE was installed into mask programmable ROMs. This meant that it was impossible to replace the code at the locations the processors vectored to when doing a reset. This meant that deep sleep was impossible.

These days, the OS is held in flash memory, and can be replaced more easily. Most of the systems I've played with it has been possible to replace things. One big issue, however, is that the WinCE boot loader has a different interface to the kernel hand-off than uboot or redboot. This can be replaced, but can be harder because of protected boot blocks.... I've not reflashed the latest

Comment From my mail server... (Score 1) 543

I've been using a Pentium III 550MHz machine as my mail server for a long time. I installed FreeBSD 4.4R on it when I got it, and other than upgrading the system to Ultra160 disks in 2003 or so, and the OS often, it has been my faithful mail server for about a decade. It is now running the latest FreeBSD 7.x-stable.

% kenv | grep reldate
smbios.bios.reldate="01/15/99"

It has only been in the past 6 months that I've thought about replacing it. It just can't handle the load of spam I get, plus spamassassin and a couple other anti-spam counter-measures. Each message takes about 5 seconds to process on this old iron, and once I went north of 10k messages per day, I noticed the queues starting to grow... While I've also put in place some cheaper rejection rules that have helped bring the queue lengths down. It is slated to be replaced by a harperton 3.4GHz box as soon as I can find the cycles to migrate everything over to a jail on it.

Prior to using this machine, my mail server was a 486DX2/66 with 32M of RAM that I used from about 1995-2002....

"If it ain't broke, don't fix it."

Warner

Comment Re:They're going to do it anyway. (Score 1) 703

Well, if they learn safe habits as teenagers, then they are more likely to practice safe habits as adults. We are sexual creatures, and we do our children a big disservice by not teaching them about sex when they are young. People marry, get divorced, etc. It is a reality of the culture today. Knowing about condoms isn't going to make you more likely to cheat on your wife/husband. It isn't going to make you more or less likely to get a divorce. Those problems come from other areas and pathologies. Pretending that the only time people have sex is when they are teens is insane.... this is a life-long learning issue. One that does society as a whole a big disservice. The Lord taught us certain ways to behave. Be he also taught us that all sinners must be forgiven, and through him they will know God and be saved. Judge not, lest ye be judged, as that old book goes.

Yet, it is ok for a bunch of moralizing do-gooders to damage society in the name of religion and morality? Give me a break. You don't learn morality by always being good. You learn morality by getting burned sometimes when you are bad, even if you learned all about it before you got burned. Bah.

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