From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: xah lee Newsgroups: gmane.emacs.devel Subject: Re: paths are sensative to double separators Date: Thu, 19 Mar 2009 17:38:07 -0700 Message-ID: References: <20090319015037.GC6695@reforged> <20090319.064244.95961919.hanche@math.ntnu.no> Reply-To: xah@xahlee.org NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary=0016e644d6ae6729d9046582217e X-Trace: ger.gmane.org 1237509506 16426 80.91.229.12 (20 Mar 2009 00:38:26 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 20 Mar 2009 00:38:26 +0000 (UTC) Cc: emacs-devel@gnu.org To: Harald Hanche-Olsen Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Mar 20 01:39:44 2009 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1LkSlx-0001VU-Ky for ged-emacs-devel@m.gmane.org; Fri, 20 Mar 2009 01:39:41 +0100 Original-Received: from localhost ([127.0.0.1]:56479 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LkSka-0006wR-UD for ged-emacs-devel@m.gmane.org; Thu, 19 Mar 2009 20:38:16 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LkSkV-0006uy-TP for emacs-devel@gnu.org; Thu, 19 Mar 2009 20:38:11 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LkSkT-0006uA-TM for emacs-devel@gnu.org; Thu, 19 Mar 2009 20:38:11 -0400 Original-Received: from [199.232.76.173] (port=44007 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LkSkT-0006u5-OK for emacs-devel@gnu.org; Thu, 19 Mar 2009 20:38:09 -0400 Original-Received: from yx-out-1718.google.com ([74.125.44.158]:43771) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LkSkT-000777-6Y for emacs-devel@gnu.org; Thu, 19 Mar 2009 20:38:09 -0400 Original-Received: by yx-out-1718.google.com with SMTP id 3so564279yxi.66 for ; Thu, 19 Mar 2009 17:38:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:reply-to:in-reply-to :references:date:message-id:subject:from:to:cc:content-type; bh=C6yCl1TSfmWvxTuTPmOliFRmUEP0EThCF30gh6IkUK0=; b=O6oQJ9L8rn7nrJ3xoVPgdDwCkxIB/nYy4HEi4vboNPLzSoqj4TA0+5iSK49MkTBWRk iJsCuWaQvNRKYp1ik2ekQCNB+d+NCVF/QIAf2RgkhsIHcD+4xu48nlTqYygedZdVD9On 0XNFmKgJ6wyIY8bAiCMb32Z0BRVJq1LubpzxA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:reply-to:in-reply-to:references:date:message-id :subject:from:to:cc:content-type; b=WMmevJQYPY1d4ytjS0VzxxkitKEyXHjffRYsdv6nV8B1KFcPbp7UD31Etwv4EGVpu1 rFxzeNIgu25jE9MGIusAYOu4PTkson0Deu9Hz3IZ8/beeJhZhDQ+4FXaqtPdvZtSU2wH VYrAvSIT4MMCzMA18u5pyTmxBkUa15j1ZS9qI= Original-Received: by 10.100.43.14 with SMTP id q14mr3465959anq.60.1237509487405; Thu, 19 Mar 2009 17:38:07 -0700 (PDT) In-Reply-To: <20090319.064244.95961919.hanche@math.ntnu.no> X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 2) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:109710 Archived-At: --0016e644d6ae6729d9046582217e Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Thanks all for the correction. Xah On Wed, Mar 18, 2009 at 10:42 PM, Harald Hanche-Olsen wrote: > + xah lee : > > > in unix-like OSes, double slash is effectively taken to mean root. > > e.g. /foo/bar//baz.el would mean /baz.el > > This convention is somewhat rooted in unixes. > > Actually, I believe posix says the exact opposite: Multiple slashes > are equivalent to a single slash, except at the head of the path, > where a double slash may have a different meaning. (On the Apollo > machines of old, running domain/os, a leading double slash indicated > the "network root", so you could specify //hostname/foo/bar to get > /foo/bar on the host named hostname. It seems they took the Sun slogan > "the network is the computer" to its logical conclusion.) > > Miles Bader gave a different explanation for emacs's behaviour. It > seems odd to me that an interactive feature (a good one, too) should > influence how path names are interpreted in code, however. > > - Harald > > PS. On those old Apollos, we changed root's home directory from / to > /. in order to avoid being surprised by programs that constructed > paths as $HOME/foo/bar. > --0016e644d6ae6729d9046582217e Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Thanks all for the correction.

=C2=A0Xah

On Wed, Mar 18, 2009 at 10:42 PM, Harald Hanche-Olsen <hanche@math.ntnu= .no> wrote:
+ xah lee <xahlee@gmail.com>:

> in unix-like OSes, double slash is effectively taken to mean root.
> e.g. /foo/bar//baz.el would mean /baz.el
> This convention is somewhat rooted in unixes.

Actually, I believe posix says the exact opposite: Multiple slashes are equivalent to a single slash, except at the head of the path,
where a double slash may have a different meaning. (On the Apollo
machines of old, running domain/os, a leading double slash indicated
the "network root", so you could specify //hostname/foo/bar to ge= t
/foo/bar on the host named hostname. It seems they took the Sun slogan
"the network is the computer" to its logical conclusion.)

Miles Bader gave a different explanation for emacs's behaviour. It
seems odd to me that an interactive feature (a good one, too) should
influence how path names are interpreted in code, however.

- Harald

PS. On those old Apollos, we changed root's home directory from / to /. in order to avoid being surprised by programs that constructed
paths as $HOME/foo/bar.

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