Dirk -- Fortunately, the issue with zip corruption (in dealing with files over 1 gig) is well documented in multiple web locations with test results. I don't know the code for Zip, so I can't speak to exactly where in the source the corruption occurs, but based upon my knowledge of compression tools, I would assume that the checksum value in the Zip standard isn't large enough. RAR and WinRAR (other compression tools based upon Tar) both completely support the ZIP spec. The point that I'm trying to make is. "It's not the Zip tool, it's the Zip specification ."
The RAR spec is a lot more stable for large archives, as is the TAR spec. Just a note on what advantages the RAR format has : - ZIP uses LZW compression (with perhaps some enhancements). RAR goes one step further using pattern compression, ideal for multimedia data which already uses some form of compression. - RAR has easy-to-use segmenting options - RAR incoporates some error checking which will flag an archive as bad if there's even a bit that's out of place. - RAR also allows a recovery record which can be used to retrieve files even when an archive is damage. - RAR offers solid archiving (files encoded in one go) which gains a bit of space. The downside to this is that the whole archive needs to be decompressed to extract just one file. - RAR archives have better passwording although I'm sure that there are utilities that can be used to crack them. - RAR Authenticity verification is a very handy feature that allows you to check where an archive came from. - RAR can conserve original file dates. - RAR takes into account NTFS file permissions. - RAR allows you to store paths and reproduce them on a destination machine. In short, RAR is more secure and more evolved compression standard. Found the following testing results (WinAce vs WinRAR vs WinZip) at SoftPedia... http://news.softpedia.com/news/WinAce-VS-WinRAR-VS-WinZip-17365.shtml Scroll down to the Details section at the bottom of the article -- For those of you who would still like to know some details about these tests here are some important facts: The testing was done using two computers, one with a 3200 AMD64 processor, the other one with a 1500 Pentium processor. The results mentioned above were from a tiff file, a mov file and a wav file. WinAce compressed the video file in 17-18 seconds to 188KB. To compress the audio file to 46.6MB it took 48 seconds at maximum compression and 24 seconds at normal compression. The image file was compressed at 47.9MB in 44 seconds at normal compression and 47 seconds at maximum compression. Please notice the fact that the although compressed to the maximum, the file size did not change significantly. WinRAR compressed the mov file to 458KB in 17 seconds at maximum compression and to 399KB in 14 seconds at normal compression. The wav was archived in 18-19 seconds to 44.9MB at maximum compression and 45.9 at normal compression. The tiff file was compressed in 47 seconds to 47.6MB. In 6 seconds, WinZip archived the same video file to 2.05MB at maximum compression and 5.59MB at normal compression in 3 seconds. Using bzip2 compression the audio file was shrunk to 59.2MB in 30 seconds for maximum compression and to 61.7MB in 9 seconds using normal compression. As for the image file, using again bzip2 compression, it was archived to 47.7MB in 27 seconds at maximum compression and in 7 seconds using normal compression. Personally, both for personal AND business use, I switched over to RAR (and WinRar) exclusively over three years ago. RAR (and WinRAR) both create self-extracting archives. Also, what Zip calls "spanning" (or compressing to multiple volumes) is perfectly supported in Rar. If you don't want to give up the Zip ghost (and presuming that the SE-Zip can be re-created from the original files), try zip-spanning. If I remember correctly, the first file will be an exe, and the other parts will be zip files. Best of luck. Barry Smith -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dirk Napierala Sent: Friday, September 19, 2008 9:59 AM To: cygwin@cygwin.com Cc: EVERS,DIRK; ZELL,VOLKER Subject: Problem to open big selfextracting Zip files from bash Hi there, We discovered an issue trying to open big selfextracting zip files. Trying to do so result in the following error: ./*selfextracting_zipfile*.exe bash: ./*selfextracting_zipfile*.exe: Cannot allocate memory This only happens to huge files (guess above 1.5GB size) Smaller once are working fine. This issue happens on the current version available for download 1.5.25-15 and also with the new 1.7.0 (base-files version 3.7-1)(thanks to Volker Zell providing us this one for testing) If we are using an older version instead (1.5.18 base-files version 3.6-1) this issue doesn't show up. We tried the same selfextracting zip file on each of the above mentioned versions on a Dell Optiplex GX280 with 2GB memory. After discussing this issue with Volker Zell he mentioned to send this incident to your mailing list. Hopefully someone can assist us with that and provide a fix. Best Regard Dirk Napierala -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
