What is a Unix Executable File? Why is it doing this?

[Greg_Reez]

From time to time when I recieve files from clients, my mac calls them a kind of file called a Unix Executable File. When I look at the kind of file in Finder or "Get Info", it says its a Unix Executable file. Most of the time I know exactly what kind of file it is, a font file, psd, ai, even a jpeg, so I can go to the program and choose File>Open.

From time-to-time I'm unsure what format the file is, so I can't necessarily go to the program and do a File>Open. I sound "incapable" when I go back to a client and asked them what format the file is in. I included a pic of my latest problem.

I received a Quark file from a client and the Quark file as well as the packaged fonts and some photos are coming back as Unix Executable Files... I didn't have quarkxpress so I had to go back to my client and ask what type of file it was... I hate doing that.

Whats going on?

[ElDiabloConCaca]

What's happening is that Mac OS X can't read the file's resource fork (and, since there's no extension on those files either, it can't even "guess"), and therefore doesn't know what the file is. This doesn't happen with files with extensions most of the time, because even if a Word document lost its resource fork (type/creator codes, specifically) information, it could still use the .doc extension to associate the file with Word.

One of two things happened:

1) The files originated from a Windows machine (or some non-Apple operating system) and no extension was put on the file. Windows machines know nothing of reading/writing Mac-compatible resource forks.

2) The files originated on a Mac, but were either transferred with a protocol or compressed with a program that ignores or strips files of that resource fork information.

There's not much you can do to get around the problem without teaching the clients new tricks. They should use a compression (.zip usually works) that preserves resource fork information, or store the files on a file system that retains this information (MS-DOS format = yuck for resource forks... FAT32, NTFS both seem to do ok with it most times).

How did these files specifically come to you? How were they transferred? Had they been compressed? If you can describe (in detail) the route they took from hard drive to hard drive, CD to CD, network to network, we may be able to pinpoint where, exactly, the resource fork info was lost and find a workaround.

[Greg_Reez]

How did these files specifically come to you? How were they transferred? Had they been compressed? If you can describe (in detail) the route they took from hard drive to hard drive, CD to CD, network to network, we may be able to pinpoint where, exactly, the resource fork info was lost and find a workaround.

These particular files came to me through email, in a zipped folder, and I downloaded them to my desktop, then extracted them. They typically come from the sender, to my entourage inbox, or my web browser mail. There isn't exactly a lot of detail involved that I can give you. And they aren't always zipped files. If it is a jpeg, and I know it is a jpeg, but it doesn't have a file extension included, I can add the jpeg extension and it'll open up fine when double-clicked on.

At least I have an "idea" of whats happening, this time is a little more frustrating than most since they are font files and I can't install them to view the client's file properly.

[artov]

Problem is (more or less) obvious: Unix programs are

1. Files that do not have extension (or they are named "a.out", but since there can be only one a.out, they are either renamed or compiled already using a different name)
2. They have execution ("x") mode on, which means they can be run

Since Windows knows nothing about execution mode, files in ZIP archives normally end with execution mode on.

Following worked fine: I copied a JPG file (a photo of my grand father's old smoke sauna) to file with no extension ("img") and put its x mode on ("chmod +x img). Now, Finder thinks it is Unix excutable file.

But, when you check the file type using "file" command on Terminal.app, it says: "img: JPEG image data, JFIF standard 1.01". This is because file command tries to read the file content, and check what the file really is.

[Natobasso]

Your mac is probably misreading the quark file. Try giving them the .qxd dot extension and see if they open.