Open Radar

 
Summary:
When a zip file contains entries that describe a directory instead of a file, they cannot be expanded with OSX's standard tool (Archive Utility) for this task.

Attached is an example zip file that won't uncompress. (http://files.tempel.org/zlib/rdar_27398797/zlib128-dll.zip)

Steps to Reproduce:
Double click the attached file in the Finder.

Expected Results:
It should get uncompressed, or at least the user should be told that he needs a different zip tool to handle this file.


Actual Results:
File does not uncompress, user gets an error message that is not very helpful:

Error 1 - Operation not permitted


Version:
10.11.5, 10.12 beta 4

Notes:
The attachment is the official zlib source code, which is the default compression format for the zip format. This zip file is from the zlib.org website, and its maintainer is Mark Adler who wrote the first zip tool. Mark has uploaded a new version without dir entries now.

Yet, this is still a problem for many other zip files on the net.

If a Mac user double clicks a zip file, and he gets an "Operation not permitted" error, it suggests to him that it's his fault somehow, or that the file may be corrupt.

Both is misleading and therefore bad communication with the user.

Same goes for opening encrypted zip files, BTW. There, too, the user should be told there other apps can solve this instead getting an error that suggests the file is corrupt.