Re: Finding empty directories

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

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>     I want to test if a directory is empty or not and I've thought
> that I could test for the expansion of dirname/*(DN[1]).
> 
>     Anyway I was wondering if is there a better way of doing that

	dirname(N-/l2)

(That's "ell two" as in "link count is two".)  I suppose if you already
know it is a directory, the (/) is redundant.

In some older versions of zsh you may need to do something funky to get
the parenthesized part to be interpreted as glob qualifiers, because in
those versions qualifiers are interpreted only when a metacharacter is
part of the pattern.

>     I would like to test if a filename correspond to a dangling
> symlink, too. I can find dangling symlinks using **/*(-@), but if I
> just have a file listing, how can I test if a file is a dangling
> symlink or not?

What do you mean by "just have a file listing"?  Except as noted above for
older versions, you can always append a glob qual, as in file(N-@).

> I've found that doing the following test:
> 
>     [[ -h file && ( -r file || -d file ) ]]
> 
>     will only return true for a symlink that really points to a file
> or a directory, and false otherwise, but I'm not sure if this is a
> proper way or if it will fail miserably on some obscure case :? In
> fact, I'm not sure if '-r' and '-d' follow symlinks by default :?

Yes, -r and -d use stat(2) rather than lstat(2), but you probably want

	[[ -h file && ( -f file || -d file ) ]]

You could also do something like

	zmodload zsh/stat
	{ stat +link bar && ! stat +nlink bar 2>/dev/null } >/dev/null