From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,6482d0ae6dcb1b4c X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-09-26 09:52:09 PST Message-ID: <3D933A6B.5000105@cogeco.ca> From: "Warren W. Gay VE3WWG" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.0.1) Gecko/20020823 Netscape/7.0 X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: if file exist References: <3d9245da.259420486@news.cis.dfn.de> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 26 Sep 2002 12:48:43 -0400 NNTP-Posting-Host: 198.96.47.195 X-Complaints-To: abuse@sympatico.ca X-Trace: news20.bellglobal.com 1033058921 198.96.47.195 (Thu, 26 Sep 2002 12:48:41 EDT) NNTP-Posting-Date: Thu, 26 Sep 2002 12:48:41 EDT Organization: Bell Sympatico Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed1.cidera.com!Cidera!torn!webster!nf1.bellglobal.com!nf2.bellglobal.com!news20.bellglobal.com.POSTED!not-for-mail Xref: archiver1.google.com comp.lang.ada:29358 Date: 2002-09-26T12:48:43-04:00 List-Id: Nick Roberts wrote: > On 23 Sep 2002 06:38:22 -0600, Kilgallen@SpamCop.net (Larry Kilgallen) > strongly typed: > >>On some operating systems the existence of a file for which the user >>lacks read permission cannot be detected. A general solution for >>detecting unreadable files is not possible. On most file systems, when you don't have the permission(s) to read the _directory_, you cannot determine if the file exists or not (within that directory). This is because the directory itself is unreadable by you, and intentially so! So this is another example of how a general solution is not possible, and this applies to _most_ O/S in use, where security at the directory level is possible. -- Warren W. Gay VE3WWG http://home.cogeco.ca/~ve3wwg