The last time I checked (a few years ago, when the cable really sucked in my house), you could buy them from Radio Shack. I don't have a cable modem, so I can't comment on how it works with data transmissions, but it's great for the TV.
My housemate and I just built one for my my room, except I used a lab countertop that school was throwing out and I used a bunch of 2x4's to make 5 legs on the desk (two front legs, three in the back).
Aside from the minor grime and scratches from past-life accidents in an electronics lab, it's great, it's the perfect height, and if I want drawers, I can put the file cabinets below it or next to it, without being constrained to their heights.
Cygwin used to (and may still) do this on win32 filesystems to figure out unix-esq permissions. It can take forever, even on small directories (I have noticed significant delays on directories with a bunch multi-gigabyte files). All in all, it's an easy hack, but it hurts.
Re:Bounded pointers, etc.
on
Memory Leaks
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· Score: 1
You might be interested in reading about the Unisys A-Series Mainframe architecture. The hardware does automatic bounds checking on arrays (and with support of the operating system, kill your program off if it tries to touch something it's not supposed to). The only recent public document that I know of is the architecture support reference manual at:
Unfortunately, that doucment is quite dense (and you're going to have to remove the lameness filter modifications). The A-Series actually uses a structure called an ASD (actual segment descriptor) to store information about the base address, length and type of data in the array, among other things. Of course, the processor can take a look at that data in parallel with accessing data in the array (and throw an exception before committing any changed data), so it has almost no performance cost (aside from reading the ASD, which is probably on par with the cost of loading the array length into a register at the beginning of a loop).
More food for thought: the architecture also has additional "tag" bits on every data word. These give some primitive type information (e.g. code, single-precision real, array element, ASD, etc...) . The processor will not allow a program to arbitrarily change data in a code segment, or things such as return addresses on your stack. I don't know if there are any other machines around today that still have this attribute (if anyone knows of some, please post!). For example, it makes a lot of the recent buffer overflow attacks that we see a moot point, since a string transfer operator would not be allowed to touch the stack frame!
I just bought a copy of Acrobat in order to make PDFs with forms. I haven't seen any free software that has this capability yet. Does anyone know of anything that can do this?
I get a fairly large number of forms from an unnamed government agency that likes to scan their forms as bitmaps and make them downloadable. Unfortunately, there are no text fields where information can be entered unless I doctor them with acrobat.
It will probably be similar to what happens on the national evening news (at least on ABC). You get a whole bunch of drug company commercials (heartburn anyone? I guess they show these during dinner for a reason) and then some local garbage.
That problem smells very much like your machine is waiting for a DNS lookup to complete before accepting the connection. See if your machine can reverse-lookup the machine you're telnet'ing/ssh'ing from.
The machine might be doing DNS lookups to match IP wrappers settings or just for logging purposes. Sometimes if the machine has no reverse-DNS name (e.g. common on a private home lan segment), it'll just sit there twiddling its thumbs for a long time trying to figure out of any other DNS servers in the world can figure out the name.:-)
This may sound like obvious advice, but what you should have done after you installed the tape drive and settled on a backup set was to check that you could actually restore!
It's easy to accidentally get the backup set wrong and think you're backing up things which never get copied to the tape. Just make a backup and restore it to another directory and see if what you expect is really there. Do this somewhat regularly and replace your tapes (I do it every year, but perhaps it should be more often?). This way, you haven't waited until things break to see if they work at all.
Take a look at your spam's headers. They're frequently sent through a dialup that connects to a mail relay. Whenever I receive a spam, I forward it with headers to abuse@_theisp_.com. No monitoring needed on the ISP end.
All the professors need to do is run everything you write through a spelling and grammar checker:
I have in the past let other students look at my code.
to stop them [from?] using it directly most of my varables are incorrect in one or other way, or I put syntax errors into the code, AND allwasy put my name in multiple times, I still cannot forget when the out come to 4+5 = "My name" as the final solution, and they missed to check the code. Cheets may prosper in the short time[.] But they are cheeting themselfs in the future[.]
Pretty soon your server will be demanding a larger salary and upward career paths in your corporate structure. Just imagine when you need HR to go out and hire a new computer for you.
That balding mouse cursor that you have will give a whole new meaning to PHB!
Basically every component sits in a socket that has long pins that are square-shaped (instead of circular). These go through the board and you strip the ends off of 30-guage wire and "wrap" them around the pins (using a special wirewrap tool or gun). It's not pleasant, but it's definitely better than soldering, at least for prototyping where you need to make a bunch of temporary connections.
This is the second announcement of Microsoft's intention to not support a "hot" peripheral connection mechanism. They announced the same thing with BlueTooth earlier this month (in this article).
I think it is probably wise that they are waiting for it to shake out, as there will are currently disagreements as to what the specification means in some places. It is probably better to have vendor-supplied support that works with the devices that are important to you, instead of a half-baked implementation that is stuck in the OS and works with nothing.
I don't quite see how this would tell you if your web server is up, unless you happen to notice that IE timed out and gave you a nastygram to that effect. It puts an awful lot of trust into the user who is staring cross-eyed at the screen until the box crashes.:-)
Not to mention, zephyr predated ICQ/AIM by far (most of the C source files are copyrighted 1988). It's a unix-based instant-messaging system developed by MIT which uses kerberos for authentication. It has not only private messages, but "classes" which allow you to broadcast messages to a group of individuals.
The interface (when using X11) is through a window with a list of users and you send discrete messages to your destination. The messages appear in separate windows on the receiver's display. The implementation doesn't appear to be meant for internet-wide use, but it is still in heavy use at CMU and MIT (where cross-realm zephyr is enabled so we can lob messages at each other).
They do a lot of systems/software integration and support work for government and private industry (in particular with banks, airlines and the insurance industry).
In addition, you're probably interested in things that you can touch. They have always made mainframes and the software to go with them. There are two lines of machines: the OS2200 Series from the Sperry-Univac side of the company and the A-Series from the Burroughs side. Their latest machine (mentioned in another post) is the ES7000, a 32-way Intel box that can be partitioned into up to 8 independent machines in the same chassis (it will be able to run Itanium chips alongside P3's, when they are available).
Disclaimer: I play with the big-boy toys (A-Series) at Unisys, but I do not speak for them. That's what their webpage is for.
I could easily imagine a program similar to webwasher (or junkbusters, if that's more to your liking) which acts as a proxy between your browser and the web server. If it detects a Click-Me-Cuz-Im-A-Moron-Who-Likes-To-Make-Your-Bro wser-Drool-Until-You-Read-My-Ads page, it might not give the page back to the browser, instead it will intercept the response and issue the click (or, alternatively, ignore the JS timeout) and return the final destination (or a redirection) page to your browser.
Granted, this would be more complex than the webwashers of today, but I don't see anything technologically impossible about it (after all, web servers already can redirect us with simple HTTP headers). The fact of the matter is that the content providers do not (and should not) have complete control over the client's computer. Unless they can use bigger webserver resources by stalling their sends (for, say, enough time to read the ad at the top of the page), then there isn't much they can do.
Take a look at itanium. Sure, it'll run slowly with 32-bit code, but not businesses simply can't recompile everything for the new processor. In many cases, they probably don't even have the source code to do so (e.g. if they use 3rd party libraries from a party that ended a long time ago). If you are suggesting that companies can do this port, it's non-trivial. If you have ever gotten sloppy in C and casted a pointer as an integer, then your code will eventually bomb on IA64, because ints are still 32-bit, but pointers are 64-bit (at least on Win64). That's just one of many gotchyas. Ouch.
It's an HTTP header. Check the HTTP 1.1 RFC, around page 116. HTTP is a generic application-level protocol that is frequently used to transfer text/html files, but also Content-types of image/jpeg and other useful data formats.
Even high-speed people mind waiting if you have a complex page!
Take a look at www.microchip.com. On every page they serve, they have a unobtrusive link called "Page Options" at the top where you can choose what page you want to get: text only, graphics or Java frame. As it turns out, I use all three versions from my university ethernet connection, depending on if I want the heavy-duty search in Java (like a MSFT help search, index, etc box), I just want to browse (I'll use graphics) or I really need something fast (text-only). It's not polite to NOT give these choices to the user!
It works great! I don't know how much more it costs them to do this, but it definitely makes for happy customers. Each version is based off a different root directory on the server and all three are probably generated automatically without the web designer having to think twice.
As far as having something else to do, generally it's looking at one or two other active Netscape windows.
A fair number of my engineering professors at Carnegie Mellon (where 802.11 has been around for a long time) have added clauses to the coversheet of their tests that goes something along the lines of:
No calculators, PDAs, laptops or wireless devices allowed.
On open-book tests, I have yet to see a laptop allowed on the test. On the other hand, one of my psychology professors said that she would love to have every student use a laptop to type up the essay portions of her tests, but it's simply not feasable at this time. It would definitely require a high degree of trust, particularly in the larger lecture classes.
On the other hand, the professor and a number of students in one of my classes have laptops with wireless cards. When a discussion comes up, somebody frequently comes up with a usenet post or web page resource relating to our discussion. More than once, the professor has written slews of email to students who are sitting only a few feet from him (wireless definitely adds to this class).
This is perhaps one of the most useful sites in today's world of technobabble:
www.acronymfinder.com. It lists 19 different meanings for "SMT", none of which are Simultaneous MultiThreading!:-)
Slashdot Mirror
The last time I checked (a few years ago, when the cable really sucked in my house), you could buy them from Radio Shack. I don't have a cable modem, so I can't comment on how it works with data transmissions, but it's great for the TV.
NPR reported that this section of the pentagon was recently renovated and many people had not yet moved back into their offices.
My housemate and I just built one for my my room, except I used a lab countertop that school was throwing out and I used a bunch of 2x4's to make 5 legs on the desk (two front legs, three in the back).
Aside from the minor grime and scratches from past-life accidents in an electronics lab, it's great, it's the perfect height, and if I want drawers, I can put the file cabinets below it or next to it, without being constrained to their heights.
The LX with Linux can decode an MP3 if you downsample to 22.1KHz or decode in mono. Otherwise, it's just choppy.
;-)
It's a great little machine, just slow. It makes a nice X server.
Cygwin used to (and may still) do this on win32 filesystems to figure out unix-esq permissions. It can take forever, even on small directories (I have noticed significant delays on directories with a bunch multi-gigabyte files). All in all, it's an easy hack, but it hurts.
http://public.support.unisys.com/aseries/docs/HMPN X05_SSR461_SSP4/PDF/70126610.PDF
Unfortunately, that doucment is quite dense (and you're going to have to remove the lameness filter modifications). The A-Series actually uses a structure called an ASD (actual segment descriptor) to store information about the base address, length and type of data in the array, among other things. Of course, the processor can take a look at that data in parallel with accessing data in the array (and throw an exception before committing any changed data), so it has almost no performance cost (aside from reading the ASD, which is probably on par with the cost of loading the array length into a register at the beginning of a loop).
More food for thought: the architecture also has additional "tag" bits on every data word. These give some primitive type information (e.g. code, single-precision real, array element, ASD, etc...) . The processor will not allow a program to arbitrarily change data in a code segment, or things such as return addresses on your stack. I don't know if there are any other machines around today that still have this attribute (if anyone knows of some, please post!). For example, it makes a lot of the recent buffer overflow attacks that we see a moot point, since a string transfer operator would not be allowed to touch the stack frame!
I get a fairly large number of forms from an unnamed government agency that likes to scan their forms as bitmaps and make them downloadable. Unfortunately, there are no text fields where information can be entered unless I doctor them with acrobat.
It will probably be similar to what happens on the national evening news (at least on ABC). You get a whole bunch of drug company commercials (heartburn anyone? I guess they show these during dinner for a reason) and then some local garbage.
A bunch of people ran antenna wires above the ceiling tiles towards the edge of the building if they were in the middle. It helped a bit.
The machine might be doing DNS lookups to match IP wrappers settings or just for logging purposes. Sometimes if the machine has no reverse-DNS name (e.g. common on a private home lan segment), it'll just sit there twiddling its thumbs for a long time trying to figure out of any other DNS servers in the world can figure out the name. :-)
It's easy to accidentally get the backup set wrong and think you're backing up things which never get copied to the tape. Just make a backup and restore it to another directory and see if what you expect is really there. Do this somewhat regularly and replace your tapes (I do it every year, but perhaps it should be more often?). This way, you haven't waited until things break to see if they work at all.
Take a look at your spam's headers. They're frequently sent through a dialup that connects to a mail relay. Whenever I receive a spam, I forward it with headers to abuse@_theisp_.com. No monitoring needed on the ISP end.
That balding mouse cursor that you have will give a whole new meaning to PHB!
Here is a picture of a wire-wrapped board:
http://www.ece.cmu.edu/~ee545/f00/12/xedni.html
Basically every component sits in a socket that has long pins that are square-shaped (instead of circular). These go through the board and you strip the ends off of 30-guage wire and "wrap" them around the pins (using a special wirewrap tool or gun). It's not pleasant, but it's definitely better than soldering, at least for prototyping where you need to make a bunch of temporary connections.
I think it is probably wise that they are waiting for it to shake out, as there will are currently disagreements as to what the specification means in some places. It is probably better to have vendor-supplied support that works with the devices that are important to you, instead of a half-baked implementation that is stuck in the OS and works with nothing.
The CONTENT tag is formatted as Seconds;url
I don't quite see how this would tell you if your web server is up, unless you happen to notice that IE timed out and gave you a nastygram to that effect. It puts an awful lot of trust into the user who is staring cross-eyed at the screen until the box crashes.
The interface (when using X11) is through a window with a list of users and you send discrete messages to your destination. The messages appear in separate windows on the receiver's display. The implementation doesn't appear to be meant for internet-wide use, but it is still in heavy use at CMU and MIT (where cross-realm zephyr is enabled so we can lob messages at each other).
In addition, you're probably interested in things that you can touch. They have always made mainframes and the software to go with them. There are two lines of machines: the OS2200 Series from the Sperry-Univac side of the company and the A-Series from the Burroughs side. Their latest machine (mentioned in another post) is the ES7000, a 32-way Intel box that can be partitioned into up to 8 independent machines in the same chassis (it will be able to run Itanium chips alongside P3's, when they are available).
Disclaimer: I play with the big-boy toys (A-Series) at Unisys, but I do not speak for them. That's what their webpage is for.
Granted, this would be more complex than the webwashers of today, but I don't see anything technologically impossible about it (after all, web servers already can redirect us with simple HTTP headers). The fact of the matter is that the content providers do not (and should not) have complete control over the client's computer. Unless they can use bigger webserver resources by stalling their sends (for, say, enough time to read the ad at the top of the page), then there isn't much they can do.
Take a look at itanium. Sure, it'll run slowly with 32-bit code, but not businesses simply can't recompile everything for the new processor. In many cases, they probably don't even have the source code to do so (e.g. if they use 3rd party libraries from a party that ended a long time ago). If you are suggesting that companies can do this port, it's non-trivial. If you have ever gotten sloppy in C and casted a pointer as an integer, then your code will eventually bomb on IA64, because ints are still 32-bit, but pointers are 64-bit (at least on Win64). That's just one of many gotchyas. Ouch.
It's an HTTP header. Check the HTTP 1.1 RFC, around page 116. HTTP is a generic application-level protocol that is frequently used to transfer text/html files, but also Content-types of image/jpeg and other useful data formats.
Take a look at www.microchip.com. On every page they serve, they have a unobtrusive link called "Page Options" at the top where you can choose what page you want to get: text only, graphics or Java frame. As it turns out, I use all three versions from my university ethernet connection, depending on if I want the heavy-duty search in Java (like a MSFT help search, index, etc box), I just want to browse (I'll use graphics) or I really need something fast (text-only). It's not polite to NOT give these choices to the user!
It works great! I don't know how much more it costs them to do this, but it definitely makes for happy customers. Each version is based off a different root directory on the server and all three are probably generated automatically without the web designer having to think twice.
As far as having something else to do, generally it's looking at one or two other active Netscape windows.
On the other hand, the professor and a number of students in one of my classes have laptops with wireless cards. When a discussion comes up, somebody frequently comes up with a usenet post or web page resource relating to our discussion. More than once, the professor has written slews of email to students who are sitting only a few feet from him (wireless definitely adds to this class).
This is perhaps one of the most useful sites in today's world of technobabble: www.acronymfinder.com. It lists 19 different meanings for "SMT", none of which are Simultaneous MultiThreading! :-)