[vwnc] [7.6] Compression-Zip - Writing capability
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[vwnc] [7.6] Compression-Zip - Writing capability
 
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Hello. |
Re: [vwnc] [7.6] Compression-Zip - Writing capability
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Dear Tom,
loading the Smalltalk Archive parcel in my vanilla 7.6
installation works fine. You'll find tar.gz writing support and examples in
class TarGzArchiver.
HTH
Helge Von: [hidden email] [mailto:[hidden email]] Im Auftrag von Gruenewald, Tom Gesendet: Donnerstag, 13. November 2008 11:08 An: VWNC Betreff: [vwnc] [7.6] Compression-Zip - Writing capability Hello. _______________________________________________ vwnc mailing list [hidden email] http://lists.cs.uiuc.edu/mailman/listinfo/vwnc |
Re: [vwnc] [7.6] Compression-Zip - Writing capability
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In reply to this post by Gruenewald, Tom
For private purposes, I have a small project of my own that supports
reading of PKZIP archives, i.e. the "famous" and wide-spread *.zip file format. Although I am pretty far with the internal format, I never had the need to complete that for writing (compressing files into an existing archive). The basic hurdle is understanding some meta-records in the PK ZIP. Unlike gzip which simply compresses contents of a single file without source file information, the PK ZIP format includes information for each file stored in the archive, including file date and file attributes etc. What I mean is that understanding the "freaky" APPNOTE.TXT is essential. Checking whether someone in the community has implemented it is ok. But if not, there is no simple way other than implementing the full format documented in this note. Otherwise you will end up in ZIP archive files that are not compatible with all those reader or uncompressing tools. For the issues with Smalltalk Archives I can tell that is is not yet decided but very much likely that it will be part of the product in future. Most recently, some fixes have been published internally, so it is a good idea to contact Cincom Support. Send your request with usual details on the problems (stack dump, example files etc.) Regards Holger Guhl -- Senior Consultant * Certified Scrum Master * [hidden email] Tel: +49 231 9 75 99 21 * Fax: +49 231 9 75 99 20 Georg Heeg eK Dortmund Handelsregister: Amtsgericht Dortmund A 12812 Gruenewald, Tom schrieb: > > Hello. > > We are starting with VisualWorks 7.6 right now. I was quit happy, > because I thought I can now easily handle ZIP archives. > But Compression-Zip only supports uncompressing files. Not to compress > them to ZIP archives. > > Link: http://www.cincomsmalltalk.com/publicRepository/Compression-Zip.html > > *Does anyone know a package or a public project which implements that?* > > I like to add files and directories to ZIP archives. > > Something like: > > * | archive |* > * archive := Archive new: 'c:\temp\compressed.zip'.* > * archive add: (ArchiveEntry new: 'c:\temp\file.txt')* > * compressionRate: 4.* > * archive add: (ArchiveEntry new: 'c:\temp\directory')* > * compressionRate: 4.* > * archive close.* > > And don't refer me to > http://www.pkware.com/documents/casestudies/APPNOTE.TXT. :-)) That is > to freaky. > I have already checked the classes InflateStream and ZLibInterface. > But so much I've understood, they can only compress streams and not > build ZIP archives. > They don't support the archive header information. > > I also tried to generate tar.gz archives. The TAR file support should > be available as part of the SmalltalkArchive support in > preview/parcels/Smalltalk Archive.pcl. > But I get an exception, when I file in the parcel file via the parcel > manager. > > Any answer would be nice. Thank you for your support. > > Best regards, > Tom Grünewald > > ________ > > Carl Zeiss Industrielle Messtechnik GmbH > Softwareentwicklung/Software Development > > T o m G r ü n e w a l d > > 73446 Oberkochen, Germany > tel: +49.7364.20-8541 > fax: +49.7364.20-4800 > email: [hidden email] > http://www.zeiss.de/imt > > Carl Zeiss Industrielle Messtechnik GmbH, Carl-Zeiss-Straße 22, 73447 > Oberkochen > Aufsichtsratsvorsitzender: Dr. Dieter Kurz > Geschäftsführer: Dr. Rainer Ohnheiser, Felix Hoben, Hanspeter Mürle > Sitz der Gesellschaft: 73446 Oberkochen, Deutschland > Handelsregister: Amtsgericht Ulm, HRB 501561 > USt-IdNr.: DE 811 515 346 > > ---------------------------------------- > This message is intended for a particular addressee only and may > contain business or company secrets. If you have received this email > in error, please contact the sender and delete the message > immediately. Any use of this email, including saving, publishing, > copying, replication or forwarding of the message or the contents is > not permitted. > > ------------------------------------------------------------------------ > > _______________________________________________ > vwnc mailing list > [hidden email] > http://lists.cs.uiuc.edu/mailman/listinfo/vwnc > Holger Guhl -- Senior Consultant * Certified Scrum Master * [hidden email] Tel: +49 231 9 75 99 21 * Fax: +49 231 9 75 99 20 Georg Heeg eK Dortmund Handelsregister: Amtsgericht Dortmund A 12812 _______________________________________________ vwnc mailing list [hidden email] http://lists.cs.uiuc.edu/mailman/listinfo/vwnc |
Re: [vwnc] [7.6] Compression-Zip - Writing capability
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Holger Guhl escreveu:
> For private purposes, I have a small project of my own that supports > reading of PKZIP archives, i.e. the "famous" and wide-spread *.zip file > format. Although I am pretty far with the internal format, I never had > the need to complete that for writing (compressing files into an > existing archive). The basic hurdle is understanding some meta-records > in the PK ZIP. Unlike gzip which simply compresses contents of a single > file without source file information, the PK ZIP format includes > information for each file stored in the archive, including file date and > file attributes etc. > What I mean is that understanding the "freaky" APPNOTE.TXT is essential. > Checking whether someone in the community has implemented it is ok. But > if not, there is no simple way other than implementing the full format > documented in this note. Otherwise you will end up in ZIP archive files > that are not compatible with all those reader or uncompressing tools. > For the issues with Smalltalk Archives I can tell that is is not yet > decided but very much likely that it will be part of the product in > future. Most recently, some fixes have been published internally, so it > is a good idea to contact Cincom Support. Send your request with usual > details on the problems (stack dump, example files etc.) > Regards > mean the low level stuff in Smalltalk) or if we should just seek an alternative of using a DLL (like Info-ZIP) and have just wrapper code in VW? -- Cesar Rabak GNU/Linux User 52247. Get counted: http://counter.li.org/ _______________________________________________ vwnc mailing list [hidden email] http://lists.cs.uiuc.edu/mailman/listinfo/vwnc |
Re: [vwnc] [7.6] Compression-Zip - Writing capability
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Thanks for the hint on Info-ZIP. I' ll have a look.
What I need(ed) for my project is any interface, either reasonable complete DLL or an EXE with satisfying command line interface. I agree with you that it is *not* a good idea to implement it if there is some decent implementation available. Normally, I never write code like that on my own. It is tedious and errorprone to redo an implementation of file format reader/writers. But at the time I started it (around December 2002) I was not aware of any free code for it. (Of course, I did not reimplement the decompression, but just reused the Compression-ZLib parcel.) Cheers Holger Guhl -- Senior Consultant * Certified Scrum Master * [hidden email] Tel: +49 231 9 75 99 21 * Fax: +49 231 9 75 99 20 Georg Heeg eK Dortmund Handelsregister: Amtsgericht Dortmund A 12812 Cesar Rabak schrieb: > Holger Guhl escreveu: > >> For private purposes, I have a small project of my own that supports >> reading of PKZIP archives, i.e. the "famous" and wide-spread *.zip file >> format. Although I am pretty far with the internal format, I never had >> the need to complete that for writing (compressing files into an >> existing archive). The basic hurdle is understanding some meta-records >> in the PK ZIP. Unlike gzip which simply compresses contents of a single >> file without source file information, the PK ZIP format includes >> information for each file stored in the archive, including file date and >> file attributes etc. >> What I mean is that understanding the "freaky" APPNOTE.TXT is essential. >> Checking whether someone in the community has implemented it is ok. But >> if not, there is no simple way other than implementing the full format >> documented in this note. Otherwise you will end up in ZIP archive files >> that are not compatible with all those reader or uncompressing tools. >> For the issues with Smalltalk Archives I can tell that is is not yet >> decided but very much likely that it will be part of the product in >> future. Most recently, some fixes have been published internally, so it >> is a good idea to contact Cincom Support. Send your request with usual >> details on the problems (stack dump, example files etc.) >> Regards >> >> > I wonder if it is a good idea at all implementing the full format (I > mean the low level stuff in Smalltalk) or if we should just seek an > alternative of using a DLL (like Info-ZIP) and have just wrapper code in VW? > > _______________________________________________ vwnc mailing list [hidden email] http://lists.cs.uiuc.edu/mailman/listinfo/vwnc |
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