5,642 reputation
11333
bio website inspirehep.net/…
location Duchy of Grand Fenwick
age 43
visits member for 5 years, 3 months
seen Sep 15 at 20:32

Experimental nuclear and particle physicist. These days I'm teaching, but I've spent a lot of time on nucleon structure in fixed target electron scattering and neutrino oscillations using reactors and beam sources.


Mar
26
revised Replacing a Macintosh SE hard-drive
added 155 characters in body
Mar
26
answered Replacing a Macintosh SE hard-drive
Mar
20
revised Kill program after it outputs a given line, from a shell script
added 136 characters in body
Mar
20
answered Kill program after it outputs a given line, from a shell script
Feb
11
comment Is there something like hardlinks that split into separate files on modifications?
The general scheme is called "copy on write". I am not aware of any file systems that do that, but it might help with searching.
Feb
5
comment Linux command line argument variations
"widget gets the argument -fizz or --fizz exactly as it is written" Well, after alias substitution, variable substitution, glob expansion and history substitution.
Jan
20
comment Are there ASCII characters that have the same keyboard input for both PC and Mac?
Er..."a" is a character from the ASCII set as are "|", "2", "Q" and "%". Are you asking about non-printing characters? There are better ways to strengthen a password than that, and they are less prone to weird system dependencies.
Jan
20
comment Are there ASCII characters that have the same keyboard input for both PC and Mac?
I don't know the Windows way, and the "same purpose" comment was intended at a pretty high level: to get characters which don't have a simple representation on the keyboard, and as an alternate shifting key for programs that want a lot of hot-keys.
Jan
20
comment Are there ASCII characters that have the same keyboard input for both PC and Mac?
The option key on the Mac serves roughly the same purpose as the alt key on a Windows box (i.e. option-u, u makes ü, option-s makes ß, option-`, a makes à, etc...), though they certainly don't map precisely together.
Jan
20
comment Are there ASCII characters that have the same keyboard input for both PC and Mac?
You seem to be conflating concepts from several (many?) different levels of interpretation. Hardware, character set, OS level interpretation and program level interpretation. I think you need to be much more precise about what you are asking. Note, that almost all the ASCII characters use the same keystrokes on Macs and Wintel boxes, but that just the Latin alphabet, Arabic numerals a bit of punctuation and some control codes. Almost everything that you have to jump through hoops to enter is not ASCII.
Jan
12
comment Hardware/IO Bottlenecks
A poorly written piece of code will stall the pipeline over and over waiting for data to arrive from RAM. Nothing is getting done while that happens, so the code takes longer to finish. It really does affect the speed of a computation.
Jan
10
awarded  Good Answer
Jan
9
answered Why do I get duplicated entries in my $PATH?
Jan
9
comment Hardware/IO Bottlenecks
The question is really ill-specified. It always depends on what you propose to do.
Jan
9
comment Hardware/IO Bottlenecks
RAM speed (as opposed to cache speed) matters a lot when you're doing medium sized computation. I've gotten a order of magnitude on occasion just be changing a program to make better use of the cache (matrix summation is a classic example of this kind of thing).
Jan
7
comment How do I log all UNIX shell commands submitted by all users?
I alert user would be able to disable this be resetting the variable and because it is executed "prior to issuing each primary prompt" this fact would not be logged.
Jan
6
comment Which malfunctions cause old computers to slow down and crash?
This would be somewhat enhanced by pointing out the importance of environment regulations against lead content: leaded solder doesn't do this, but to protect the water supply we either need to eliminate it (hard) or insure the proper disposal of all electronic kit (even harder).
Jan
6
awarded  Mortarboard
Jan
6
comment Which malfunctions cause old computers to slow down and crash?
@Daniel: There are other types of capacitors which don't share all the failure modes of the electrolytic variety. So why do people use electrolytic ones at all: cost and availability---electrolytics are cheap, compact in the few millifarad to few farad range, and easy to get. I have no idea how much of an increment to expect.
Jan
6
comment Which malfunctions cause old computers to slow down and crash?
@Daniel: It should help.