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Date: Fri, 26 Apr 2013 16:17:27 +0200
From: Jilles Tjoelker <jilles@stack.nl>
To: Joshua Isom <jrisom@gmail.com>
Subject: Re: Some improvements to rm(1)
Message-ID: <20130426141726.GA85955@stack.nl>
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On Fri, Apr 26, 2013 at 08:33:54AM -0500, Joshua Isom wrote:
> On 4/26/2013 7:23 AM, Eitan Adler wrote:
> > Yes, rm's functionality can be fully replicated by find.

> As well as anything using -R.

Emulating other -R things using find becomes quite slow when you don't
want to impose {PATH_MAX} limits or open up symlink-based race windows
because the only safe option is -execdir UTILITY {} \;. Any find command
based on -exec, -print or -print0 passes pathnames which are subject to
{PATH_MAX} limits and directories concurrently replaced with symlinks.

The construct -execdir ... {} + is unusably broken in older FreeBSD
versions and gives no advantage compared to -execdir ... {} \; in recent
-CURRENT.

With -L, this is not a new problem because symlinks are followed anyway
and the underlying code (fts(3)) always imposes the {PATH_MAX} limit in
that case.

The -delete primary is safe like -execdir.

I'm not entirely sure about this because the rm(1) patch is simple and
the new syntax is fairly clear.

-- 
Jilles Tjoelker