Unzip only updated files

command linezip

Is there a way to unzip a zip file into a directory, but only do so for updates files (I mean the compressed files inside the zip)?
I have a huge directory of files there, and only about 20% are different.

Preferably using command line, but it's optional. I use Windows XP.

Thanks.

Best Answer

With the winzip commandline addon, you can use the -n option:

-n

Unzip only newer files. This option updates existing files if the archived file is newer and creates new ones if they do not already exist.
wzunzip -n "c:\my documents\spring2007.zip" c:\semesters\spring05  
This example will extract, from c:\my documents\spring2007.zip, ONLY those files that are newer than the files that currently exist in c:\semesters\spring05 OR that do not already exist in the c:\semesters\spring05 folder.

You might want to combine it with the -o option - "Overwrite existing files without a prompt (automatically reply "Yes" to each overwrite prompt)."

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Macos – Terminal unzip outside default directory

The specific answer to your question is no. The unzip that ships with OS X has no way to change directories in the zip on the fly. One thing to note however, is that zip is not 'creating the directory'. It is part of the archive. A properly created zip archive will not have this issue if you are controlling the creation process:

$ ls -l
total 0
-rw-r--r--  1 bsmith  staff  0 Sep 30 22:01 b
-rw-r--r--  1 bsmith  staff  0 Sep 30 22:01 c
$ zip -r a.zip .
  adding: b (stored 0%)
  adding: c (stored 0%)
$ cd ../b
$ unzip ../a/a.zip
Archive:  ../a/a.zip
 extracting: b                       
 extracting: c                       
$ ls -l
total 0
-rw-r--r--@ 1 bsmith  staff  0 Sep 30 22:01 b
-rw-r--r--@ 1 bsmith  staff  0 Sep 30 22:01 c

Windows – How to recursively extract zip files on Windows including deletion

ExtractNow does this. See http://www.extractnow.com/Usage.aspx#process. Beware that Chrome and maybe other browsers flag the app as malware/spyware. The author maintains that this is just from the installer and points to a portable version for those who don't want the installer (although Chrome also calls that zip file malicious).

Unzip only updated files

Best Answer

`-n`

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