1. Forum
  2. Newsgroups
  3. comp.os.linux.misc

  • Extracting Multisegment Zip Archives

    From Lawrence =?iso-8859-13?q?D=FFOliveiro?=@ldo@nz.invalid to comp.os.linux.misc on Fri Dec 19 01:20:30 2025
    From Newsgroup: comp.os.linux.misc

    This page
    <https://open3dlab.com/project/cba26de0-d1ee-4daa-abbb-00fb16a75358/>
    contains some multipart archives in .zip and .7z format.

    Try as I might I could not use zip and unzip to make any sense of the
    multipart .zip, .z01 etc files. There were suggestions in the man page
    to concatenate them together and use the -Z or -ZZ options to fix them
    up, but all I got was failure.

    Finally I discovered that 7-zip can not only extract its own multipart archives, it can handle .zip ones as well. Painlessly.
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From c186282@c186282@nnada.net to comp.os.linux.misc on Fri Dec 19 02:41:51 2025
    From Newsgroup: comp.os.linux.misc

    On 12/18/25 20:20, Lawrence D’Oliveiro wrote:
    This page <https://open3dlab.com/project/cba26de0-d1ee-4daa-abbb-00fb16a75358/> contains some multipart archives in .zip and .7z format.

    Try as I might I could not use zip and unzip to make any sense of the multipart .zip, .z01 etc files. There were suggestions in the man page
    to concatenate them together and use the -Z or -ZZ options to fix them
    up, but all I got was failure.

    Finally I discovered that 7-zip can not only extract its own multipart archives, it can handle .zip ones as well. Painlessly.

    7-Zip *is* the improved utility.

    Multi-parts ... try deliberately shifting to the dir
    where all the parts are stored and THEN running it.

    Alas, I've yet to find a way to get 7z to use more
    advanced encryption methods. ZIP encryption is kinda
    crappy, many pw busters out there for it.

    Got well into corporate backup methods back in the
    day. Could NOT find anything I liked. So, wrote my
    own. Each individual file could be zipped or not
    and then put through AES encryption. Gotta zip BEFORE
    encryption btw or you get big fat files - encrypted
    files are binary 'white noise' and zippers can't zip.

    Also, for safety, did all the encryption LOCALLY in
    a temp dir before sending the files to local, or
    especially 'cloud', storage. I do NOT trust 'cloud
    storage' providers ... esp not NOW when there is
    big $$$ selling content to AI companies as 'training
    material'.


    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From John Ames@commodorejohn@gmail.com to comp.os.linux.misc on Fri Dec 19 08:05:32 2025
    From Newsgroup: comp.os.linux.misc

    On Fri, 19 Dec 2025 02:41:51 -0500
    c186282 <c186282@nnada.net> wrote:

    Each individual file could be zipped or not and then put through AES encryption. Gotta zip BEFORE encryption btw or you get big fat files
    - encrypted files are binary 'white noise' and zippers can't zip.

    Did that back at another job, some years ago - the client IIRC was a fleet-services payment processor, so we dealt with sensitive customer
    info at fairly high $ amounts, but either their backend or ours was too antiquated for more secure methods, so payment info was sent in a plain-
    text spreadsheet that we zipped up, PGPed, and...sent over unencrypted
    FTP :/

    (Hoo boy were we not PCI-compliant at that place - we'd brought on a
    guy for compliance years before, but he was one of the most dedicatedly
    useless people I've ever had the displeasure to work with. When I got
    laid off we *still* weren't compliant, and since he was axed as well I
    imagine they never were. To nobody's surprise, the company folded a few
    years later.)

    When the client got paranoid about that setup, we ended up *printing
    out and mailing* the spreadsheets o_O

    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From jayjwa@jayjwa@atr2.ath.cx.invalid to comp.os.linux.misc on Fri Dec 19 20:20:36 2025
    From Newsgroup: comp.os.linux.misc

    Lawrence D’Oliveiro <ldo@nz.invalid> writes:

    Finally I discovered that 7-zip can not only extract its own multipart archives, it can handle .zip ones as well. Painlessly.
    Yup. Pretty handy, especially when you need to send files to people on
    other platforms and also when you don't want the metadata to go along
    with it. Hopefully you have the full one that used to be Windows-only
    and not the p7zip one? If you can, get the little assembler it wants to
    build. That version is much faster than the one built without.

    7-Zip (z) 24.09 (x64) : Copyright (c) 1999-2024 Igor Pavlov : 2024-11-29
    64-bit locale=en_US.utf8 Threads:8 OPEN_MAX:1024, ASM

    It should say "ASM" at the end, as above.
    --
    PGP Key ID: 781C A3E2 C6ED 70A6 B356 7AF5 B510 542E D460 5CAE
    "The Internet should always be the Wild West!"
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Lawrence =?iso-8859-13?q?D=FFOliveiro?=@ldo@nz.invalid to comp.os.linux.misc on Sat Dec 20 02:47:45 2025
    From Newsgroup: comp.os.linux.misc

    On Fri, 19 Dec 2025 20:20:36 -0500, jayjwa wrote:

    Hopefully you have the full one that used to be Windows-only
    and not the p7zip one?

    Standard Debian package.

    <https://packages.debian.org/trixie/7zip>
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From rbowman@bowman@montana.com to comp.os.linux.misc on Sat Dec 20 06:15:19 2025
    From Newsgroup: comp.os.linux.misc

    On Fri, 19 Dec 2025 20:20:36 -0500, jayjwa wrote:

    7-Zip (z) 24.09 (x64) : Copyright (c) 1999-2024 Igor Pavlov : 2024-11-29
    64-bit locale=en_US.utf8 Threads:8 OPEN_MAX:1024, ASM

    fwiw. Fedora and Ubuntu have

    7-Zip 25.01 (x64) : Copyright (c) 1999-2025 Igor Pavlov : 2025-08-03
    64-bit locale=en_US.UTF-8 Threads:8 OPEN_MAX:1024, ASM


    Linux Mint 22.2 is 23.01 without the ASM.
    --- Synchronet 3.21a-Linux NewsLink 1.2