Behavior on KDE3.5 is
1. prints application/octet-stream

2. prints application/x-zerosize

3. prints application/x-zerosize on the file from (2) and 
application/octet-stream on a file with size > 0

/usr/bin/file does

1. prints error exits with error code

2. prints application/x-empty

3. prints application/x-empty for the zero sized file and an error message for 
a file with length. Return value is 0 in both cases.

Presently, on gentoo kde 3.5.3, I get the following:

1.  Error code == 1, error msg "--info:  Invalid parameter/option"
2.  ditto
3.  ditto

Is this expected behavior?  

Syntax has changed, instead of "xdg-mime --info" use "xdg-mime query filetype"

1. Now returns with 2 --> "One of the files passed on the command line did not 
exist."

With regard to 2 and 3: There is no guarantee that results in different 
environments will be the same, is there a reason why the cases described 
should be treated as special case?

That said, we can do a check for 3 and return an error code for "file not 
readable"

Am I doing something wrong?  I get this on kde:

$ ./xdg-mime query foo.bar
foo.bar:  Invalid parameter/option
$ echo $?
1

try
$ ./xdg-mime query filetype foo.bar

Okay, the original cases described seem okay:

1.  
 $ ./xdg-mime query filetype foo.bar
 Error:  You must specify an existing file.

2.  
 $ touch foo.bar
 $ ./xdg-mime query filetype foo.bar
 application/x-zerosize

3.
 # chmod 000 foo.bar
 $ ./xdg-mime query filetype foo.bar
 application/x-zerosize

However, according to the man page, xdg-mime also supports a 'default'
parameter, and this seems to be misbehaving:

 $ rm foo.bar
 $ ./xdg-mime query default foo.bar
 Error:  You must specify an existing file.

 $ touch foo.bar
 $ ./xdg-mime query default foo.bar
 basename: missing operand
 Try `basename --help' for more information.

 $ file foo.bar
 foo.bar: empty

But it seems okay with valid file content:

 $ echo 'hello world' > foo.bar 
 $ file foo.bar 
 $ ./xdg-mime query default foo.bar
 kwrite.desktop
 $ file foo.bar 
 foo.bar: ASCII text

(In reply to comment #3)

> With regard to 2 and 3: There is no guarantee that results in different 
> environments will be the same, is there a reason why the cases described 
> should be treated as special case?

It seems to me that the whole point is to have consistant well defined behavior
across distributions, otherwise applications may count on one behavior but find
another. However, perhaps I have highlighted some exceptional cases here that
should be documented as such.

My goal was not to treat thease cases as special, but just call attention to
what I thougt was a normal case that was not working properly.

The case below has been fixed in CVS for Beta1 (at least with KDE) 
 
 $ touch foo.bar 
 $ ./xdg-mime query default foo.bar 
 basename: missing operand 
 Try `basename --help' for more information. 

Proposed resolution:
1. (fixed already)
2. WONTFIX
3. Provide custom error message if file is not readable.

Created attachment 6382 [details] [review]
File check functions

Possible extension to xdg-utils-common.in for checking the
availability/permissions on input and output files

Created attachment 6383 [details] [review]
Improved patch

There is already an exit_failure function for missing files, using that instead

Created attachment 6384 [details] [review]
Using check_input_file in xdg-mime

Looks good, please commit.

Committed the two input files, but left the resulting file untouched since my 
xmlto breaks the description text. Probably some locale setting problem

Thanks, will regenerate file.

Final resolution
1. FIXED
2. WONTFIX
3. FIXED