How do I access Unix Executable Files?

Don M August 13, 2013

I recently needed to reload some files that I archived a few years ago. When I went after them they had all been changed into Unix Executable File. This has occurred several times since I upgraded to OS X. It has happened to files of all types and they won’t open, and I can’t retrieve any data with any of the file tools I have available.

Can anyone help?

  1. Bruce E
    August 13, 2013 at 1:16 pm

    "...since I upgraded to OS X." What operating system were you using when you archived these files? What tool did you use to create the archive? Did you create self-extracting archives with the tool?

  2. Jan F
    August 13, 2013 at 9:58 am

    My first guess would be that those files were saved without their file extension and OS X just assumes they are unix executables.

    I suggest going into "Finder > Preferences", Advanced and enable to show all file suffix. Then take a look if those files are missing them and add the appropriate one.

    Other possible options are them being Windows executables, unknown file types respectively having no application installed that could open them.

    • Bruce E
      August 13, 2013 at 1:14 pm

      Unix, Linux and the BSDs do not assume anything about files. If it says it is a Unix Executable File it is because it contains the "magic numbers" in the header that positively identify it as an executable file. Microsoft's operating systems are the only ones that assume that the file's extension is a positive identifer of the file type in most cases although it does some verification based on the header contents in some cases (Windows PE files, DLLs, etc).

      If a file cannot be identified by the header, it is generically considered 'data' under *nix operating systems.

    • Jan F
      August 16, 2013 at 9:56 pm

      Yes, that is until you install applications within OS X.

      If for example you install The Unarchiver and select all archive types any EXE file will be identified as "Windows Self-Extracting Archive".

      And equally weird things happen for any file extension OS X cannot identify. My Keypass DB (.kdbx) is also identified as Unix Executable File since I don't have Keypass installed on my Mac.

      An Outlook.pst file? The very same, Unix Executable File - that is regardless of me having Outlook 2011 installed which can actually import PST files...

      Please don't assume OS X acts like any other UNIX system out there, because it doesn't ~ even if Apple wants it to.