Questions tagged [7zip]

"7z" or "7-Zip" may refer either to the open-source 7z compression container format or to the file name of the executable program of the same name that is the flagship implementation of the compression format. Both are GPL-licensed and under active development.

"7z" or "7-Zip" may refer either to the open-source 7z compression container format or to the file name of the executable program of the same name that is the flagship implementation of the compression format. Both are GPL-licensed and under active development.

The 7z format is a compressed archive file format that supports several different data compression, encryption and pre-processing algorithms. The LZMA SDK 4.62 was placed in the public domain in December 2008. The latest stable version of 7-Zip and LZMA SDK is version 18.05. The MIME type of 7z is application/x-7z-compressed.

The 7-Zip program is an open source file archiver. 7-Zip operates with the 7z archive format, but can read and write several other archive formats. The program can be used from a command line interface, graphical user interface, or with Microsoft Windows shell integration. 7-Zip's development began in 1999, and it is actively developed by Igor Pavlov. It is related to a cross-platform port, p7zip. 7-Zip is free software distributed under the GNU Lesser General Public License (LGPL). It was the winner of the SourceForge.net 2007 community choice awards for "Technical Design" and for "Best Project".

7z has an open architecture, so it can support any new compression methods. Now the following methods are integrated to 7z:

  1. LZMA: Improved and optimized version of LZ77 algorithm
  2. LZMA2: Improved version of LZMA
  3. PPMD: Dmitry Shkarin's PPMdH with small changes
  4. BCJ: Converter for 32-bit x86 executables
  5. BCJ2: Converter for 32-bit x86 executables
  6. BZip2: Standard BWT algorithm
  7. Deflate: Standard LZ77-based algorithm
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How to delete a file from multiple zip archives using 7-Zip

I have a thousand zip archives that all contain a file I want to remove. I can get 7Zip to remove them one file at a time from the command line: 7z d -r archive.zip *.pdf but how would I apply that across all the files, which are themselves grouped…
user3409415
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What's the correct email attachment MIME type for a zipped and password protected file?

It's zipped and password protected with 7zip, should the mimetype be "application/7zip", or just "data/binary"? Something else?
MikeN
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How to include files and folders with 7zip powershell

Im trying to make my powershell script zip up a few files and folders. At the moment I can make my script either zip all files (with no folders included), or zip all files with folders included but to the wrong path. An example would be if I have a…
G3TH
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7-Zip command-line switch

Is there a 7-Zip command-line switch that prevents the filenames from echoing to the screen as they are added to the archive?
KTLind
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Recursive Unzipping with 7z.exe

I stumbled across the below line as a means of extracting every .zip file in every subfolder. FOR /F "usebackq" %a in (`DIR /s /b *.zip`) do 7z.exe e %a I've tried this on a WinXP cmd.exe prompt and I get the error: "a was unexpected at this…
SparkyNZ
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How do i check if a file is password protected via 7zip?

I am using 7zip (command line) to look at zip/rar/7z files. I essentially check how many files and what extension it has. Than... i got to password protected files. When the entire file is password protected (so you can not look at the filenames or…
user34537
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Creating a logical folder structure when creating a 7-Zip archive via the command-line

I have been archiving files using the "DotNetZip" library using code like this: var files = new [] { new { file = new FileInfo(@"C:\_test\Data\Testing\data.txt"), source = "Data" }, new { file = new…
Enigmativity
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How to validate multi part compressed (i.e zip) files have all parts or not in C#?

I want to validate multipart compressed files like Zip because when any part missing for compressed files then it raises an error, but I want to validate it before extraction and different software creates a different naming structure. I also refer…
Hiren Jasani
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extracting multiple files with 7zip & creating a folder for each

I have like 300 zip files (but may get other kind of archives in the future) in a folder and I need to unzip each one in a subfolder of the archive name. I've tried native 7zip options in command line but nothing worked yet, did not get any luck in…
Tracto
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How to resolve 7-zip's 'Warnings: Headers Error' from .zip created by Ant build?

I have code for creating zip file in ant build script. When file is…
Prem
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Extracting a multi-part zip with Python

I'm looking for a way to use python to extract multi-part zip files (eg blah.zip, blah.z01, blah.z02, blah.z03 etc) on Windows without any prerequisite installs (like 7zip). This question has been asked already but the only answer there says to use…
TheCatOfWar
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Unzipping files in a faster way than using the java.util.zip in Android

I need unzip a .zip file of 2.5mb(1087 files - *.html, *.css and *.db) in android, i have used java.util.zip, it works fine, but i need improve the performance, the unzip process last 1.10 minutes, i need reduce this time. I have followed some…
Jhon
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Decompressing a file like 7zip with Java

I need to open a compresed file (zml, i don't couldn't find information about that extension) like 7zip does it with java. I have a zml file, if I open it with 7zip it asks me for the password, then I put the password and can open the file. I need…
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How do I use the 7z sdk to extract rar/zip files (C++)?

I'm trying to write a small, cross-platform comic book reader (Qt / C++). I don't care what's already out there, I know there are some. My problem is that I need to read the comic book formats, which are renamed rar and zip files. The documentation…
Lunarcloud
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How to get size of packed file in 7-zip archive

I'm using SevenZipSharp and it has Size property in ArchiveFileInfo struct, that "Gets or sets size of the file (unpacked)". How can I get size of packed file in archive?
a1bT
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