Subject: Re: COMPAT_AOUT removal
To: Robert Elz <kre@munnari.OZ.AU>
From: Todd Vierling <>
List: current-users
Date: 08/07/2000 08:02:16
On Mon, 7 Aug 2000, Robert Elz wrote:

:   | I've yet to hear compelling arguments as to why it's detrimental.
: And that "ls /usr" using an a.out version of ls (like perhaps an old
: colorls binary) doesn't really list /usr is not detrimental ?

: It would be nice to change that as well.   Perhaps only the very first
: pathname lookup might use the magic redirection for some emulations
: (just enough to find a suitable - for those emulations where the
: source of the applicable can be obtained and modified to look for
: its libraries in some other place than /usr/lib (or /lib))

One of the best strategies proposed in the past is to provide two sysctl
knobs per-emulation:

....translate_dir: translate /emul lookups when open(2)ing a directory
....translate_creat: translate /emul lookups when creating a new inode

The defaults for these can be `smarter' about the contained emulation,
depending on whether the target OS has the ability to work well without
directory translation (...if you put /emul/*/usr/lib in, for

These have been the two sticking points with /emul, and they have zero
`special' relationship with COMPAT_AOUT.  For instance, if I do `ls /usr'
using a Linux colorls, I get the same behavior.

-- Todd Vierling <>  *
-- Speed, stability, security, and support.  Wasabi NetBSD:  Run with it.