Welcome to the MacNN Forums.

workerbee · Dec 13, 2005, 12:30 PM

A friend has just sent me a file that has no name whasoever. It appears as an attachment blank icon with no text in mail.app. Saving this file to the desktop results, again, in a blank file (white paper) icon that has no name. Changing the name is impossible, there's no text input showing up.

LS in Terminal shows the file as ??.
FielBuddy and PathFinder both show the file as being named " ".

It is possible to give the file a name in Finder using Get Info, but one has to delete those first two empty spaces/unreadable characters.

What sort of character would not display at all in OS X? And why can a file with a name that can't be displayed be saved to the desktop (or wherever) in the first place?

tooki · Dec 13, 2005, 12:55 PM

There are many characters that don't display, as well as literally thousands more that OS X simply doesn't have fonts for.

Can you use the Get Info window in the Finder to just Select All in the actual file name, and then delete that and type or paste in a new name?

tooki

Chuckit · Dec 13, 2005, 01:56 PM

Originally Posted by tooki

There are many characters that don't display, as well as literally thousands more that OS X simply doesn't have fonts for.

But if it didn't have the font, I'd think it would show a character-not-found glyph. It sounds like this is a carriage return or something.

tooki · Dec 13, 2005, 04:32 PM

Normally, yes. Hence why I specifically mentioned "characters that don't display", too.

tooki

CharlesS · Dec 13, 2005, 04:39 PM

It could be a non-breaking space. A non-breaking space is a character you can enter by typing option-space. It looks exactly like an ordinary space, but the system doesn't see it as one, so two words divided by a non-breaking space will get recognized as one word by the system, and thus the two words won't get separated by auto-wrap or other such features. And, a non-breaking space will show up as ?? in the Terminal.

Of course, if you want to know what it is for sure, you can just copy the character in the title into the Character Palette...

workerbee · Dec 13, 2005, 07:06 PM

Originally Posted by CharlesS

Of course, if you want to know what it is for sure, you can just copy the character in the title into the Character Palette...

How would I do that? I've copied one of the mysterious characters in the Get-Info window, and I've managed to find the character palette... but how do I paste anything into it? Pasting into the character palette search field pastes nothing. In BBEdit, pasting "it" at least shows an empty space.

Thanks for the tips.

workerbee · Dec 13, 2005, 07:06 PM

Sorry... Safari/NSsomething-or-other error double post

BTW: Anyone interested in playing around with this thing, pipe up. (Don't worry, it can be deleted in the finder and is, I hope, quite harmless: it's part of a font file that did not beam right).

tooki · Dec 13, 2005, 07:20 PM

Originally Posted by workerbee

How would I do that? I've copied one of the mysterious characters in the Get-Info window, and I've managed to find the character palette... but how do I paste anything into it? Pasting into the character palette search field pastes nothing. In BBEdit, pasting "it" at least shows an empty space.

Thanks for the tips.

Get Info (command-i) on the file. Open the "Name & Extension" section. Click in it. Select All (command-a). Type in a new name.

tooki

CharlesS · Dec 13, 2005, 07:25 PM

Here's an idea: Copy the characters, then download HexEdit (available from MacUpdate/VersionTracker) and paste the characters into the right-hand side. See what hex characters show up in the left hand side, and post them here.

f1000 · Dec 13, 2005, 07:31 PM

Yahoo! Mail allows you to preview attachments. Maybe you could forward this attachment to a Yahoo account and preview it?

tooki · Dec 13, 2005, 08:34 PM

Who go to the trouble of doing that when you could just rename it in the Finder using the instructions I gave above?

tooki

f1000 · Dec 13, 2005, 08:40 PM

Maybe he wants to add some spice to his life?

workerbee · Dec 14, 2005, 03:30 AM

Originally Posted by f1000

Maybe he wants to add some spice to his life?

hehe...
I'm perfectly aware of the fact that I can rename the file in the Finder (tooki: I did describe it in the very first post), in FileBuddy and in PathFinder. What I'm interested in is

Why is it possible to have a filename that no software can display?
What are the characters that do not display?
Could this not somehow possibly be misused (set another icon for the file, and you have a totally invisible file)?

workerbee · Dec 14, 2005, 03:33 AM

Originally Posted by f1000

Yahoo! Mail allows you to preview attachments. Maybe you could forward this attachment to a Yahoo account and preview it?

The content of the file are no mystery: my trusty BBEdit opens (almost) everything. As said above, it is a font file that probably suffered severe damage (think: hacked to pieces) somewhere along the way.
It's the file name I'm interested in.

workerbee · Dec 14, 2005, 03:49 AM

Originally Posted by CharlesS

Here's an idea: Copy the characters, then download HexEdit (available from MacUpdate/VersionTracker) and paste the characters into the right-hand side. See what hex characters show up in the left hand side, and post them here.

Thanks Charles -- that's what I got...
And this is what the file looks like when I select it in the Finder:

CharlesS · Dec 14, 2005, 05:08 AM

The first character, 0x16, is SYN, or "synchronous idle." According to this site, the definition of synchronous idle is:

synchronous idle character (SYN): A transmission control character used in synchronous transmission systems to provide a signal from which synchronism or synchronous correction may be achieved between data terminal equipment, particularly when no other character is being transmitted.

The second character, 0x07, is BEL, the "bell tone", which back in the good old BBS days was the character that was sent by the ISP to tell your terminal emulator to beep. It used to be typeable via control-G, which resulted in many great pranks being possible back then. For example, on an old BBS I used to be on in the early 90s, there was a bug that allowed you to be able to enter control characters by entering a carat in the subject header of an e-mail. So, you could send someone a message with a subject of ^G^G^G^G^G^G and make their computer beep a bunch of times when they received it.

Anyway, both are characters that were not intended to be used in streams of readable text, so they do not display in OS X. As a result, if you have a file name with only these characters in it, the file appears to have no name (although you can still rename it by clicking on the file and hitting the Return key).

BTW, if you type 1607 into the left side in HexEdit, and then copy the two dots that show up in the right side, and then you try to save a file in any application and paste into the "Save As" box, you should be able to make another file like the one you already have.

tooki · Dec 14, 2005, 12:27 PM

Originally Posted by workerbee

hehe...
I'm perfectly aware of the fact that I can rename the file in the Finder (tooki: I did describe it in the very first post)...

You said "but you have to delete the characters first", which you implied wasn't possible because it's not selectable. I gave you a way around this.

No need to get angry.

tooki

workerbee · Dec 14, 2005, 01:01 PM

Originally Posted by tooki

No need to get angry.

Tooki: I wasn't angry at all (wouldn't know why I should be)... sorry if that's the impression it gave.