Wikipedia:Reference desk/Archives/Computing/2006 September 21

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September 21

Microsoft excel question

Ok so I have 2 long lists in Excel, in columns right next to each other. The first list contains all the information I need, and the second list is a partially complete version of the first. How can I sort the lists to seperate out what is in the second list but not in the first list?Xcfrommars 03:15, 21 September 2006 (UTC)

What type of data is it? Anchoress 03:20, 21 September 2006 (UTC)

Just several thousand cells with text names Xcfrommars 03:22, 21 September 2006 (UTC)

Well if I understand you correctly, turn on the Data, Autofilter option, then filter the second list for 'blanks' and that'll leave you with the remainder. Or just sort the second list and it'll show the empty cells at the top. Anchoress 03:29, 21 September 2006 (UTC)

Let me get this straight - you have two lists. They are in two columns. If the two lists are in different columns, then isn' it already sorted? Or do you mean the two lists are mixed together, and spread over two columns?

It really depends on what information is on the lists. Whether it's text, numbers, combination of both...etc. But two things you can try are:

the SORT function. In which case you should put everything into one column. Then go to data-->sort. If the information is text, this will sort all the columns and arrange them alphabetically. If the data is numbers, this will sort them into order.

conditional formatting. Go to format-->conditional formatting. This allows you to tell excel to format all cells that fit a certain condition. So in the conditional formatting box, you can choose conditions and have excel do something to every cell that has those conditions (so for example, highlight every cell that fits those conditions.) You can also use the add button to add additional conditions. If the information in your cell involves numbers, then there is a lot of options you can use (like cell value is "between", "not between", "greater than"...etc). If it's text, use cell value is "equal to" and type in the text. So "cell value is equal to x" means any cell that says "x" will get formatted.

So if you're wanting to use conditional formatting - you should find something that is common to the first list but not in the second list. Then use conditional formatting on it to pick outeverything that's in the first list (things in the second list will not be affected.) Or find something that's common to cells which are ONLY in the second list, and use conditional formatting on it to pick out everything that's only in the second list. Yaksha 03:28, 21 September 2006 (UTC)

Scorewriter/MIDI problems

I am having problems with MIDI. I opened a MIDI with WMP 11 then I subsequently opened it in Sibelius (scorewriter) but playback wouldn't work. Then I opened it in MIDINotate Musician and playback still wouldn't work. I have done almost everything I know (checked my speaker, reset the MIDI driver, reset the sound sets in Sibelius, de-affiliated WMP 11 with MIDI, uninsalled WMP 11, etc.) Please help me! Thanks. --hello, i'm a member | talk to me! 03:36, 21 September 2006 (UTC)

Responses? --hello, i'm a member | talk to me! 02:55, 22 September 2006 (UTC)

Programming exercise

I read in an article that a common programming exercise given to undergrad students is to write a program that prints its own source code. As a novice programmer I'm very interested. I guess the answer is recursion of some sort, but I have no idea_{don't laugh} how to implement it. Hints, Wikipedia? - 219.93.29.135 04:45, 21 September 2006 (UTC)

It's not really recursion, as they want you to print the source code, which is a distinct file from the executable that actually "runs". (An exception would be if you were running thru an interpreter.) So, in the normal case of running an executable, it would simply have to read a file line by line and print out those lines. Quite a simple program, really. StuRat 06:02, 21 September 2006 (UTC)

Generally, the task is interpreted to specifically exclude you doing that. It has to be a self contained program. Here's a hint: consider what facilities your programming language has in it for embedding string constants in the program, particularly with regards to escape characters. -

All that said, I've taught beginning programming, and I'd never set such a task; it's a) too tough for most beginning programmers, and b) it doesn't teach the kind of skills that are actually desirable for students to have after taking "introduction to C".

There is more information on this in the Wikipedia, but on the basis that the individual concerned asked for a hint rather than the answer I'll refrain from linking to the relevant article. --Robert Merkel 06:07, 21 September 2006 (UTC)

I've had a reverse problem which is trickier, how to allow users to enter text at runtime, which then becomes part of the computer program (specifically a math formula that the program is to plot). StuRat 06:04, 21 September 2006 (UTC)

Self-modifying code is different from just graphing.. turning user input into object code is the real challenge! x_x --froth^{T C} 13:52, 24 September 2006 (UTC)

See our entry on quine for a lot of discussion of these types of programs. --Fastfission 15:49, 21 September 2006 (UTC)

moving my windows slave in my mac?

can i use my windows xp origanated ntfs filed slave drive as a slave in my osx mac computer (essentially using the slave as a big flash drive to move picture files etc back and forth) or is there an easier way to do this? (these are huge picture files... not conducive to an actual flash drive)

OSX is basically Unix/Linux. To my knowledge, NTFS drives can only be safely mounted as read-only. If you try to write to them from Unix/Linux, you risk terrible file corruption. For a common format, I still use Fat32. Both Windows and Linux safely read/write to that format. --Kainaw ^(talk) 19:23, 21 September 2006 (UTC)

information technology

give me examples f use of information technology|?

Geez, how hard can this homework question be...think of a random business or other organization. For instance, consider a school. Think of all the different ways that a school uses computers . Pick another type of organization - say a supermarket. Count the ways you can see they use computers (and modern cash registers are essentially a type of computer). Repeat until you have enough examples. --Robert Merkel 10:02, 21 September 2006 (UTC)

Antivirus on multi-OS setup

I recently got more and more problems on my computer and couldn't even re-install Win98, so I bought a new hd, connected only that and everything installed just fine. So I think I've got a virus on the other hd's. So I want to install antivirus software, but the manufacturers rarely give any info on which OS's and file systems they will work on. I use different OS's (various Linux distros, Win98 and WinXP) and file systems (reiser, ext3, fat and ntfs) to prevent the spread of viruses, eg original files on fat and backups on ext3. Does this make any sense? And do all antivirus software programs cover all file systems (and which OS had I better run it from?) or do I need to install more than one? Also, are commercial programs any better than free ones? Normally I can judge for myself, but here I can't. DirkvdM 12:44, 21 September 2006 (UTC)

From what I can understand, of your question, no, not all AV software can cover all file systems, as it has to have those file-access routines provided by a lower layer of the system, the operating system. On Windows NT based operating systems, this is handled through "IFS." On Linux, I think it is handled through modules, but I can't be sure about that. So, the problem wouldn't be finding an antivirus program that can read your hard drives, but it would be finding a driver for your operating system to allow the virus scanner to read the files. I would say that it doesn't matter which OS you use, but certain fanatics will choose an OS for you. I have heard high ratings for both BitDefender and Kaspersky, both of which have free versions. (BitDefender has BD8 for Windows free for personal use, LinuxDefender with BD8, and BD8 for Linux. Kaspersky is being distributed by AOL.) Generally, almost all virus scanners are considered "commercial." The only "free" (as in speech) ones that I know of are OpenAntiVirus (which looks like a dead project) and ClamAV. As for "free as in beer," no, generally, for your purpose of finding and / or cleaning a known infection, "free" and "commercial" are the same. Versions of virus scanners which have "free" and "commercial" branches just differ in "advanced functionality" such as realtime scanning, scheduled scanning, and pattern updates. I hope this helps! Jdstroy 19:42, 21 September 2006 (UTC)

Thanks, I'll give those a try. But I suppose I'll have to use the Linux versions because Windows doesn't see the ext3 and Reiser file systems (right?). DirkvdM 10:47, 22 September 2006 (UTC)

Probably. John Newbigin created Explore2fs and EXT2IFS, so in Windows NT/2000/XP (and the entire family of Windows NT), you can use EXT2IFS to read ext2 partitions. A quick search on Google for "Reiser IFS" reveals interesting projects going on, but I don't know if anything will work. Standard disclaimer applies. ;) Short of installing an IFS driver in Windows NT or using Explore2fs, you can, as you said, use Linux virus scanners. Hope this helps! Jdstroy 19:32, 22 September 2006 (UTC)

Right, thanks, that bit was still a bit unclear to me. I'd have to specifically install such software. So so as long as I don't do that, the backups on the ext3 partitions should be safe from any Windows viruses and as long as I don't specifically install software to read ntfs on Linux, backups ont ntfs partitions will be safe from any Linux viruses. Right? I've thought of this solution myself, and it makese so much sense that I wonder why I have never heard of it before. DirkvdM 06:35, 24 September 2006 (UTC)

Yes, that is correct. It's a good barrier. (Although, in Linux, you will probably have it shipped with an NTFS read-only driver... I don't think that has much effect with any virus.) Jdstroy 06:06, 25 September 2006 (UTC)

Electronic document storage

We are in the processing of scanning our files into the computer so the paper can be stored off-site. Some people are very nervous about this process in case the server goes down.

What is recommended as far as backing this up? Someone suggested backing up these files to DVD so they can be pulled up if there are server issues.

Any help is appreciated.

Thank you.

DVD-Rs aren't the worst way to backup files if you are not planning to change the backups much, and you are talking about backing them up primarily for the relatively short term (i.e. the next 5-10 years or so). I'd make numerous copies and store them in different places, personally. There are lots and lots and lots of ways to do data backup, depending on how much data there is, what sort of resources you have to spend, how valuable the data is to you, and so forth. If you primary concern is about having access in case of server malfunction, having backups on DVDs would probably solve it, as would having the capability to turn another computer into a backup server. What you are proposing is a somewhat unstructured repository, which for a relatively small operation (esp. one which would not need constant updating) might be sufficient (it would certainly be cheap, though whether it is easy depends on how you plan to update the backups, if you need to do that). --Fastfission 15:41, 21 September 2006 (UTC)

SQL Query

Consider the following two tables:

• Patients: MRN (Unique ID), Patient Name, ... (the rest of the fields don't matter)
• Visits: ID (Unique ID), MRN (FK to Patients), Date, SBP, DBP, ... (the rest of the fields don't matter)

I want to get a list that looks like:

MRN	SBP	DBP
C12	120	90
A33	132	105
C97	118	92

Where MRN is a list of the patients - each patient listed only once. SBP and DBP are the last value of SBP and DBP. By "last value", I mean that there are many Visits per patient and I only want the last one - the one with the most recent Date.

I've been trying to write an SQL query (postgres) to do this, but it turns out to be a very hard problem. For example, a patient may see the doctor twice in one day if he/she is in the hospital. So, you can get two SBP/DBP visits on the same day and I don't want to list any patient twice. In that situation, I just want one of them (it doesn't matter which). I have figured out how to get the last SBP/DBP for a given patient:

• select SBP, DBP from visits where ID in (select ID from visits where MRN='C12' and SBP>0 and DBP>0 order by Date desc limit 1)

As you can see - SBP/DBP is zero if it is not checked. So I had to add the SBP>0 and DBP>0 check. But, that is as far as I've been able to get. Any help will be greatly appreciated. --Kainaw ^(talk) 14:01, 21 September 2006 (UTC)

Here's a guess: SELECT MRN, SBP, DBP FROM patients INNER JOIN visits ON visits.MRN=patients.MRN INNER JOIN visits AS v ON visits.id=(SELECT ID FROM visits.MRN=v.MRN WHERE MRN='C12' ORDER BY Date DESC LIMIT 1)

Or, if that won't work: SELECT MRN, SBP, DBP FROM patients INNER JOIN visits ON visits.MRN=patients.MRN AND visits.id=(SELECT ID FROM visits WHERE visits.MRN=patients.MRN ORDER BY Date DESC LIMIT 1)

No idea if they'll work, but that's the best I've got. --Pidgeot (t) (c) (e) 17:35, 21 September 2006 (UTC)

Are you sure you don't want to list patient names in the output ? StuRat 17:50, 21 September 2006 (UTC)

The second example worked, but I had to alias patients as "a" to use it in the subselect. Of course, the subselect quardupled the time for the query compared to a simple join between the two tables. I got it on a tiny version of the tables. Now, it is running on the real tables - should be done in about 3 hours. Thanks. --Kainaw ^(talk) 18:07, 21 September 2006 (UTC)

where can i get the software for capturing a flash video from a web page to save into my hard* disk for linux ?

i wish to take a video screen shot or to capture the screen (that has video or flash) whatever i am doing in the screen.

please anyone help me to get that software for linux? or send the link!

Skype and music

Hi! I have my main audio out hole taken by my speakers. WHat can I do to simultaenously listen to music and skype, on 2 different "channels" (music:speakers, skype:headphones). Thanks! PS This is not from my CD drive, where I could use its own audio-out socket. -R.

In skype: tools -> options -> sound_devices, and pick the devices that correspond with your skype headphones and their attached mic. -- Finlay McWalter | Talk 17:14, 21 September 2006 (UTC)

How about this: What music player (Winamp?) would let me choose my output device, in this case my CD-ROM - possible? Roughly a "splitter". -R.

I think the CD-ROM's phono port is hardwired. For Skype I bought an ultra-cheapo audio card, but you can just as easily use a cheap USB phone device. -- Finlay McWalter | Talk 18:41, 21 September 2006 (UTC)

ISP Costs Around the World

Since I have the opportunity here to get info from around the world, I'm just curious as to how much both dial-up and high speed dsl costs in other countries compared to here in Canada. In fact, for all I know, one of the two (dial-up or high-speed) might be so unpopular in certain parts of the world that one is completely favoured over the other, or perhaps even that only one is even available. (I'm saying that because of my experience with renting a car in Europe...here in North America, automatic transmission is the norm, and manual is reserved either for sports cars or really, really low-end economy cars, whereas in Europe it's virtually (but not completely) impossible to rent a car with automatic transmission. I'm not sure why that's the case, but for some reason that's how things are. I'm just wondering if the same phenomenon might apply for high-speed vs. dial-up.)

In any case, what I'd really like to find out is how much it costs in various places. Here in Canada I get dial-up for about $3 a month (our dollar is worth about 90¢ US so that would amount to about $2.70 US). High speed dsl is generally about ten times that price. Something like $30-$35 US/month.

I'm just curious if there's any major difference in cost where any of you folks live. What kind of ISP service do you guys have and how much do you pay? (I'm pretty familiar with most of the major world currencies, so I can probably calculate the equivalent in Canadian dollars, but if you can, it would be great if you could express it in US$, just to save me from having to make a few dozen calculations!) Thanks! Loomis 17:49, 21 September 2006 (UTC)

In Detroit, USA, it's $10 a month for dial up via AOL (was $24 until just recently !). Yahoo! DSL is from $13 (1.5Mb/sec) to $28 (6Mb/sec). You've got us beat on dial-up, but we have you beat on DSL, it seems. StuRat 18:33, 21 September 2006 (UTC)

Good thing you clarified which Detroit you were speaking of Stu. For a moment you almost had me believing you were actually from Detroit, Khazakhstan. :-) Loomis 19:11, 21 September 2006 (UTC)

Well, not all people who read this post will know that Detroit is in the USA, so I clarified it for them. StuRat 19:41, 21 September 2006 (UTC)

This is my first time on the Computing RefDesk, so I'm sort of a newbie. Is everyone always so serious? Where are all the smiley faces? :-) The Detroit thing was a joke. I'm feeling some serious culture shock. I think I should go back to where I belong (sort of) at the humanities Refdesk. :-) Loomis 23:11, 21 September 2006 (UTC)

This has got to be the first time I've ever been called too serious at a Ref Desk. I suppose many of the questions here, like the specs on a graphics card, don't particularly lend themselves to humor. Although, I did once manage a joke about IGES (a CAD exchange format sometimes known to produce rather large files)..."a 10 Mb IGES file ? Geez, you must have had a line AND a circle in that file !". StuRat 09:16, 25 September 2006 (UTC)

this ain't the friendly misc. desk loomis, things are digital here, black/white, Vulcan. There are no jokes so straighten up your act. Jasbutal 04:58, 22 September 2006 (UTC)

Whoa Jasbutal...Straighten up my act? Not a chance. Of course I'll try my best to "fit in with the locals" so to speak. I'm not here to be a shit-disturber. But don't you ever EVER dare tell me to "straighten up my act". I'll act as I please. Loomis 06:14, 24 September 2006 (UTC)

In the UK, the best deal I could find is 2Mbps ADSL unlimited broadband for £15 a month or US$28.22 according to Google. For higher speeds prices are similar but can go up to around £20 a month (US$37.63) and include a download cap (see later). The highest speed in most cities is 8Mbps with rural areas are usually restricted to 1 or 2Mbps with some restricted to 64Kbps dial up. However, most broadband ISPs will give you a download cap of normally 1, 2 or 3 GBs per month although some are unlimited, however, if you want to go unlimited then you usually need to pay quite a bit more (£28 for 8Mbps unlimited (US$52.68) is not unusual). Dial-up is only slightly cheaper than low speed broadband (1Mbps) in most cases £14 a month or similar but there are also pay as you go dial up packages where you pay the cost of the telephone call to the ISP per second and nothing else. Also, something I've noticed is that the term "broadband" doesn't seem to be used outside the UK. It basically refers to higher speeds than dial up (but not ISDN). In the UK there are 2 main ways of getting broadband. If you live in a big city you can get DSL broadband through your cable TV and if not, the you get ADSL via the BT telephone network. 88.110.142.138 19:03, 21 September 2006 (UTC)

Ok, apparently there are a bit more variables than I had anticipated. I just want to make sure I'm comparing apples to apples here. And please indulge my ignorance of certain terms because I'm only semi-computer-literate. The dial-up that I get is about 46kps. I know, it's really slow, but you just can't beat the price. Am I correct in assuming that when you guys are talking about dial-up, you're talking in that speed-range? As for high-speed, I really have no clue how fast it is because I've never been a subscriber. Another thing about what the above poster from the UK said: "there are also pay as you go dial up packages where you pay the cost of the telephone call to the ISP per second and nothing else". It's been I while since I've been in the UK, so I don't remember, but are you saying that local calls aren't free? (as long as you pay a flat fee for the phone line of course). Maybe I misinterpreted what you said. Loomis 19:29, 21 September 2006 (UTC)

I just took his comments to mean you can pay a per minute rate for dialup, as opposed to a monthly charge. On the other hand, AOL has an 800 number (toll free) with a per minute surcharge, in ADDITION to the monthly charge for dial-up. I used this once, when I was in a town with no local dial-up number. StuRat 19:41, 21 September 2006 (UTC)

For dial-up, you need to take into account the cost of calling the dial-up as well as the service. When I was in Germany, there was no such thing as a free call. Just calling from one phone to another phone in the same building incurred a cost similar to long distance here in the U.S. - but, that was a good 15 years ago. It probably changed due to public demand by now. As for this topic, perhaps Wikipedia should have an article on Cost of Internet Access. --Kainaw ^(talk) 19:37, 21 September 2006 (UTC)

Shoot, I'd trade with all of you folks. Local numbers exist in South Carolina, but all the service charges are a bitch. DSL costs ~$28/month (not sure the speed) for basic service (BellSouth), dialup is ~$10-14/month (again, BellSouth), but can be as low as $5/month. Cable costs ~$47/month from RoadRunner, while from AOL (yes, same company, strange policy; 768k down) it is $25.90. In the north-east region, serviced by Verizon, DSL is ~$15/month for basic service (768kbps?). Also, in the urban regions, dial-up is ~50.6kbps at best, usually ~40.3-50.6kbps, with lows in ~14.4kbps. BellSouth is making a killing. :( Jdstroy 19:53, 21 September 2006 (UTC)

The theoretical top speed for dial-up is 56kbps but in practice this is never achieved. When I was on dial-up the top speed I could get was 32kbps so lucky you in that case. So yes, when I talk about dial up I talking about everything up to that speed. Telephone packages vary from provider to provider. In all cases, you have to pay a company for line rental (normally BT) which is the flat rate you are referring to. In general, local calls are not free, but they are very cheap (supposedly). If you use a "pay as you go" dial-up service the number that is dialed is a special "local rate" number (like premium rate numbers which I'm sure exist everywhere and charge you everything under the sun). Local rates will vary depending on who provides your telephone package but are normally around 1p per minute (US 2¢) during weekends and evenings at 3p per minute (US6¢) during the day. With these packages you only pay for the time you are online, so if you were online for 10 minutes at the weekend that may equate to 10p (US 19¢). So effectively, StuRats interpretation is correct, you pay per minute to the ISP and not a monthly charge. 88.110.142.138 20:04, 21 September 2006 (UTC)

Just another related question. I used to pay $10 for dial-up with my old ISP. But then my friend told me about the $3 company, and as I couldn't believe how good a deal it was, I switched as soon as I got the chance. The thing is, they told me that for an extra $3, I could get what they called the "turbo" version. Supposedly it's somehow supposed to make web-surfing, as they claimed, seven times faster. They said that while it won't affect downloading stuff, it'll just make switching pages a lot faster. In any case, I figured "what the hell, it's just another 3 bucks, I'll still be paying 4 bucks less than before, so there's really no harm in taking it, the whole thing may be a totally bogus gimmick, but we're really talking peanuts when we're talking another 3 bucks a month", and so I went for it. So now I'm actually paying $6 a month rather than $3. I'm still paying $4 less than before, and so I'm really not all that concerned. I'm just curious. It's hard to tell if surfing is really any faster, it probably is a bit, but still hard to tell. What I have noticed is that the graphics tend to be a bit poorer. I'm just wondering what your guys take on the whole thing is. Have you ever heard of such a thing? Is it just a bogus rip-off? Still, I'm not too concerned because as I said, it's $3...peanuts. If it helps, their website describing the whole thing is 295.ca . It'd be great if you guys can give me your take on this. Thanks again!

According to their site, this version of dial up would seem to replace the graphics you see with ones optimised by your ISP. Since the graphics have been replaced with smaller files, the dial up connection takes less time to download them and that's why they claim it's faster. Note that I'm only making an assumption that this is what they do from the information on their website, I can't be sure. I've never heard of anything like it before but if my assumption is correct, then it's not really a rip off as you are getting something for your money. Whether you need or want it, is another question. 88.110.142.138 20:43, 24 September 2006 (UTC)

That's actually a compressor and an image compressor. When it encounters web pages that are not compressed, it encodes them using a compressor, such as the zlib/gzip/LZ77 series. With images, it attempts to either recompress the images losslessly (again, similar idea), or, it attempts to decrease the size of the image by re-"optimizing" it, resulting in a lower quality. Generally, it reduces the image quality to produce a file that is easily compressable by the chosen algorithm. Jdstroy 06:16, 25 September 2006 (UTC)

line breaks

within the wiki software what is the code to perfom a line break? I am referring to the type of break the will prevent a new section from starting until the bottom of a captioned picture is reached.

Use <br clear='all'> --Kainaw ^(talk) 19:49, 21 September 2006 (UTC)

Thank you 158.106.50.3 20:14, 21 September 2006 (UTC)

ZIP 2.0 encryption

Hello,

Does anyone know where I can find the specification for ZIP 2.0 encryption, or a Java library for managing it? It's hard to find Java libraries for ZIP encryption, as it's usually not implemented due to the known weaknesses (yet it still takes forever to crack! ;) ). Documentation is also somewhat troublesome to find, as it's usually obscured by commercial password crackers. (Also, extra kudos to anyone who can tell me the implications that the ZIP 2.0 encryption weakness entains in terms of password recovery. I didn't find any documentation on it.) Jdstroy 19:57, 21 September 2006 (UTC)

I've cracked a few ZIPs it's not too hard and only took a few minutes! You might want to take a look at pkcrack. There's a windows binary floating around too, but that link has the source so you can see how the algorithm works.

I know that pkcrack uses a "known" attack. You must have a file from the protected zip outside of the zip. Usually this isn't too hard, especially if the readme in the zip is published on the website or something. The program brute-forces the encryption key and compares the output with the file you have. The key isn't too large (below 40 bits certainly). Don't try this on the newer securezip format, it will either not work at all or take millions of years :D (it uses 256-bit AES encryption).

By the way, one particular limitation of windows pkcrack is that every bit of your known file must be IDENTICAL to the extracted file from the zip. Windows definately doesn't do this well- it can take some careful operations (using FlashGet to download it, not copying and pasting it, etc) --froth^{T C} 14:05, 24 September 2006 (UTC)

Thanks froth. Do you know of anything that is simply brute force instead of known-plaintext, short of FastZipCrack or FCrackZip? I've used the prior and compiled and used the latter, but neither is very suitable. FZC is rather slow, and it is limited to DOS-only. FCrackZip works, but it doesn't support multiple parts. That's why I want to write my own in Java--that way, I can work it in a similar fashion as distributed.net, with a keyserver and a bunch of clients. Jdstroy 06:13, 25 September 2006 (UTC)

Brute forcing most any encryption at all these days (yes even ZIP) takes weeks to years. Known plaintext is just the most intelligent (and one of the very few feasible) cracking options available. If you're looking to encrypt (or decrypt with password input) ZIP files, you might want to see this page, this page and this page. You might also want to look for open source zip programs (there are dozens) and take a look at their code --froth^{T C} 22:27, 26 September 2006 (UTC)

I see. So the known problem with old ZIP encryption is dealing with known-plaintext? I don't have any known plaintext for the ZIP file in question (it is, indeed, using the weak "ZIP encryption"), so I either have to use brute-force or a dictionary attack. I have considered looking at the source for open code, but there doesn't appear to be anything for Java-based (which is what I use almost exclusively) ZIP encryption / decryption, so it's likely that I'll have to write my own code. Thanks for the link to PKware's details; chances are, I'll be starting from there. Jdstroy 03:38, 28 September 2006 (UTC)

Max Open Window Limit in Win 98 Running AOL

I'm getting an error that says I have too many windows open and must close some if I want to open more. This isn't true, however, as I only have a small number open. This error occurs after I've been on the comp for a while, so I suspect it's not "clearing" the record of open windows when I close them. A reboot fixes the issue, for a while. As a workaround, I'd at least like to set the max window number as high as possible. I can't seem to find that in the help files, though. So, how do I set the max open windows limit ? Also, if anyone has advice about what's the root cause of this, I'd appreciate that info, too. Thanks. StuRat 20:08, 21 September 2006 (UTC)

I think that this is related to Windows 98's handling (pardon the pun) of handles. I don't know of anything that can help with "recycling" or "garbage collecting" handles and their IDs, but usually, as you have done, restarting will help with the issue. When you use components that have many widgets or accesses to files, Windows 98 will create one handle per object, and ... well, the problem is that the handle IDs don't get recycled. At least, that's what I think happens; my knowledge of Windows 98's inner workings are fading. Jdstroy 20:32, 21 September 2006 (UTC)

It's not windows as such that's the problem, but "resources" in general. Win98 has a limit of around 16,000 active resources at any one time. These resources include concrete things like icons, menus, buttons, windows, and so on, as well as more abstract things like device contexts and font handles. If a program is well-written, closing a window will free up those resources that the window was using. Quitting a program will always free up all the resources that the program was using; the reason you need to reboot is that Windows itself isn't well-written, and you can't quit it except by rebooting. The only fix is to upgrade to a NT-based operating system: NT4, Win2k, and WinXP have essentially no limit on active resources. If you still need Win98, 98SE does a better job of managing resources than regular 98. --Serie 21:10, 22 September 2006 (UTC)

Thanks, I'm running Windows 98SE. I have seen an explicit open windows limit setting in Unix, however. Are you sure none exists in Windows 98SE ? StuRat 05:42, 23 September 2006 (UTC)

Certain. It's a hard limit of 16,384 resource handles (ie. what can fit in a single 64k real mode memory segment). --Serie 19:16, 27 September 2006 (UTC)

I find (I'm running NT4.0) that sometimes I close all the windows but they're still in the taskbar processes, and closing them there frees up a lot of space. Also, I find sometimes one or two of my IE windows (I tend to run 10 or 15 at the same time) will be using an inordinate amount of resources, and it helps to close that. Anchoress 06:37, 23 September 2006 (UTC)

Freespace?

Does anyone know of a remotely-located ("hosted") file repository system that is free? I've looked at box.net and Xythos/Sharemation, and Streamload, but there are many limitations:

• Box.net - Downtimes are often, file size limit is 10 MB.
• Streamload - Maximum file size is 25 MB, storage quota is 25 GB, limited bandwidth quota of 1 GB/month.
• Xythos/Sharemation - Total storage quota is 5 MB, bandwidth quota is 5 MB/hr.

I really like the way that Sharemation works, and, to an extent, Box.net. Sharemation provides full DAV access, while Box.net provides some support for DAV.

I want something like like DAV or iFolder, where I can connect to the service as if it were a native drive. (Too bad iFolder demo died.) I really don't like file size restrictions, but I'm not too picky with storage quotas. Bandwidth quotas are rather annoying as well, but I'm sure I can manage.

Does anyone have some good finds? (I thought about using Catacomb's databased-backed DAV, as I know of several unlimited MySQL hosts... but it's slow, and I don't have Apache httpd, even though I do have Tomcat5.)

Kudos to those who read, even more to those who answer.

Jdstroy 20:26, 21 September 2006 (UTC)

This was a while back, so I don't know if it's still available, but I used to use a site called freedrive.com for that sort of thing. You might want to take a look. But again, this was a while back. Loomis 22:57, 21 September 2006 (UTC)

Yes, I used to use that, too, but they closed. There used to be something called "isavix" that provided gzip-compressed and encrypted storage, with SSL, but they vanished, too. Thanks, no less, though. Jdstroy 23:59, 21 September 2006 (UTC)

file forge :) --froth^{T C} 22:29, 26 September 2006 (UTC)

Thanks. But it's not exactly what I'm looking for.  :( But I think I found something that might just work out for the while. I'm using Apache Tomcat and Slide from Jakarta. Slide is like the Java version of Catacomb. Hooray!

I'm still open to better suggestions, though. Jdstroy 22:09, 27 September 2006 (UTC)