Slashdot Mirror
Slashback: Zip, Language, Opportunism
Funny name, well-executed idea. YourMother writes "After almost 4 days of being offline, the social network Orkut is back online. The Orkut development team has been working nonstop since bringing it down on Sunday afternoon and quite a few new security features have been implemented to protect users information. Within the first 48 hours it was up, it gained almost 100,000 users, growing many times faster than other social networks like Friendster or Tribe. Did Google hit the social network bulls-eye?"
glinden points to a story with some more information about those security holes. "From the article, 'Sources close to Google suggest widespread XSS (cross-site scripting) hacks forced the closure of the service. It isn't clear how much personal data or communication was disclosed.'"
Playmate. Playmate, playmate playmate. An anonymous reader writes "A week after an appeals court ruling revived a Playboy Enterprises Inc. trademark infringement lawsuit against Netscape Communications Inc., the companies have reached a settlement in the case (See a ZDNet report) The terms of the settlement have not been disclosed. This puts an end to a closely watched case in the search engine advertising field. Several other lawsuits over misuse of trademarks in search engine ads are still in place. Google e.g. is embroiled in a lawsuit with Luis Vuitton regarding keyword-based ads in France and asked for a California court's ruling to back its trademark policy for AdWords after facing the threat of a lawsuit from American Blind & Wallpaper Factory Inc."
You have to admire such brave nomenclature. Michiel Frackers writes "Thanks for the link to my site, I got 3 gigabyte of traffic in a few hours! If I would have known, I would have written something in English. I have added an update about the Strangeberry product and its relation to Tivo at the URL you linked to.
I also included a link to my private blog (as www.frackers.com is more about my work in media & technology). Hopefully this clarifies some things for your readers, I did not intend to make this some kind of quest or game at all: it's just that I promised Arthur and his colleagues not to disclose what they are exactly doing, as you will understand."
And Anonymous joe writes with this link to an intriguing bit of Strangeberry speculation at the Register.
Nokia to port Python to Mobiles, not Perl An anonymous reader writes "Nokia was mistaken. In fact, El Reg reports that Python, not Perl, is the preferred language for scripting on its smartphone platforms. The availability of a Python implementation for mobile phones is part of a broader plan, including a JVM-based BASIC interpreter."
However, the Register article linked says that Perl is being considered, it's just that Python is being looked at as the primary language.
I wouldn't trust their pearls, either. Blade Leader writes "OCZ has issued a recall of OCZ Ultra 2 thermal paste after the Overclockers.com article on their lack of silver content. They blame the lack on their supplier, and claim they will be pursuing legal action."
A piece of history (or at least a piece of somethin' ...) Artemis writes "Searching along E-Bay and MikeRoweSoft.com I noticed that Mike Rowe has decided to sell the Microsoft Cease-and-Desist Letters and WIPO book he received on E-Bay. He is selling the WIPO book with the 25-page letter received from Microsoft's lawyers on January 14/2004.This inch-thick book contains copies of web pages, registrations, trade marks, other WIPO cases, emails between me and Microsoft's lawyers and much more. There are 27 annexes filled with information. This package also comes with the 25-page complaint transmittal coversheet that was sent with the inch-thick book."
What's wrong with gunzip, tar? whitefox writes "CNet News is reporting that PKWare & WinZip have settled their differences and will maintain Zip file compatibility for the foreseeable future with each supporting the other's security extensions. In addition, PKWare will include its SecureZip in the code it licenses to other software makers. This is good news in deed for users and developers alike!"
Had you read the post you would have noticed that he's got two copies, one of which he is keeping for himself.
-Kilka
If we don't believe in freedom of expression for people we despise, we don't believe in it at all. -Chomsky
Just a public sevice announcement,
by going to http://www.winzip.com/wzcline.htm you can add command line support to WINZip.
Not trying to to be a jerk, just wanting to inform people who need to use it (Corporate policies... ewww)
Sigs? We don't need no stinking sigs!
that does unpack everything only to throw away all but the file you wanted,
Well, actually it only unpacks the stuff that comes before the file in the archive. If the file in question is near the top, most of the archive is not unpacked.
Don't label something "offtopic" unless you know the topic well enough to tell what's on topic.
I'll bite:
What is Cross Site Scripting"
Actually, no. tar (Tape ARchiver) would still have to process all the crap in front to find the gzipped file.
./test1.1.tar
tar made the assumption that it was sending/receiving it's data from a sequential access device, not a random access one. This assumption heavily influenced the file format. So even on a random access device, it still has to slog through the preceeding data to get what it wants. But it has some nice advantages for data recovery. If you lose half the tape, you can still get the files back on the part you have. It doesn't matter if you only have the first half, the last half, or the middle half. As long as the complete file exist on a piece of tape you have, you can get that file back.
Because of this, tar won't even exit early if you only want one file and it's at the beginning of the archive.
Watch:
crlewis@localhost % time tar tvf test1.tar
-rw-r--r-- clewis/users 439 2004-01-13 13:41:20 win2000Serv.cfg.bz2
-rw-r--r-- clewis/users 14735 2004-01-13 13:41:20 win2000Serv.log.bz2
-rw-r--r-- clewis/users 1006 2004-01-13 13:41:20 win2000Serv.nvram.bz2
-rw-r--r-- clewis/users 342346881 2004-01-13 14:09:11 win2000Serv.vmdk.bz2
0.080u 2.280s 0:13.95 16.9% 0+0k 0+0io 191pf+0w
crlewis@localhost % time tar tvf test2.tar
-rw-r--r-- clewis/users 342346881 2004-01-13 14:09:11 win2000Serv.vmdk.bz2
-rw-r--r-- clewis/users 439 2004-01-13 13:41:20 win2000Serv.cfg.bz2
-rw-r--r-- clewis/users 14735 2004-01-13 13:41:20 win2000Serv.log.bz2
-rw-r--r-- clewis/users 1006 2004-01-13 13:41:20 win2000Serv.nvram.bz2
0.170u 2.070s 0:13.59 16.4% 0+0k 0+0io 191pf+0w
clewis@localhost % time tar xvf test1.tar win2000Serv.cfg.bz2
win2000Serv.cfg.bz2
0.170u 1.940s 0:14.54 14.5% 0+0k 0+0io 250pf+0w
clewis@localhost % time tar xvf test2.tar win2000Serv.cfg.bz2
win2000Serv.cfg.bz2
0.160u 1.970s 0:12.31 17.3% 0+0k 0+0io 250pf+0w
It takes just as long to extract a single file from the beginning or end of the archive, and they both take the same amount of time as processing the whole archive. Now, extracting the whole archive is much slower, because that big file takes a lot of bidirectional Disk I/O, but it's the same time whether it's at the begin or the end.
Now watch this, we'll "Lose" the first 15KBytes, and everything after 30KBytes.
clewis@localhost % dd if=./test1.tar bs=1k skip=15 of=test1.1.tar
clewis@localhost % ls -la test1.1.tar
-rw-r--r-- 1 clewis users 15360 Jan 29 17:53 test1.1.tar
clewis@localhost % time tar tvf
tar: This does not look like a tar archive
tar: Skipping to next header
-rw-r--r-- clewis/users 1006 2004-01-13 13:41:20 win2000Serv.nvram.bz2
-rw-r--r-- clewis/users 342346881 2004-01-13 14:09:11 win2000Serv.vmdk.bz2
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now
0.010u 0.000s 0:00.03 33.3% 0+0k 0+0io 195pf+0w
I still got back the data that existed in the part that was saved. win2000Serv.vmdk.bz2 is corrupt, but win2000Serv.nvram.bz2 is fine.
The .tar.gz and .tar.bz2 formats are "solid" archives: they enchain the files into a single archive, the .tar file, and then compress that as a whole. This allows them to achieve better compression because they can compress redundancies between files as well as within them. Zip, OTOH, is what I call a "segmented" archive: the files are individually compressed and the compressed images are enchained.
Solid archives can be smaller than segmented, but are more difficult to manipulate after the fact:
- To extract a single file from a solid archive, you have to read everything in the archive, at least up to the file you're extracting. A zip file has a directory at the end that quickly locates the desired file.
- To add, delete, or replace files in a preexisting archive, you have to decompress the whole thing, manipulate the files, and then compress the whole thing again. It can be done, but it's slow and can take up lots of disk space. Zip can do these things directly, leaving unaffected files unchanged.
- Finally, solid archives are more fragile than segmented ones. If a solid archive is damaged, everything from the point of the damage onward is lost. With zip, however, only the files at the damaged portion are lost, and subsequent files are still recoverable.
IIRC RAR can generate either a solid or a segmented archive.Zip, furthermore, has a feature that can preserve arbitrary file metadata such as NTFS file permissions. Tar, OTOH, is meant for Unix, and can only preserve metadata relating to Unix.
There's no technical reason that you couldn't create a .zip.gz or .zip.bz2 file, getting a solid archive that preserves all the metadata, but alas, you'd probably confuse most people doing that :-(
Ooh, moderator points! Five more idjits go to Minus One Hell!
Delendae sunt RIAA, MPAA et Windoze
WinZip's AES encryption is documented here. PKWare's format is apparently proprietary.