Path: utzoo!attcan!uunet!cs.utexas.edu!know!samsung!emory!mephisto!bbn.com!mips2!mwarren
From: mwarren@mips2.cr.bull.com (Mark Warren)
Newsgroups: comp.unix.wizards
Subject: Re: Hard links to directories: why not?
Keywords: ln, directories, security...
Message-ID: <1990Jul19.115622.14015@mips2.cr.bull.com>
Date: 19 Jul 90 11:56:22 GMT
References: <5222@milton.u.washington.edu> <6940@eos.UUCP>
Organization: Bull HN Information Systems Inc.
Lines: 28

In article <6940@eos.UUCP> jbm@eos.UUCP (Jeffrey Mulligan) writes:
>
>What should be the output of the last command of this sequence?
>
>mkdir dir1
>mkdir dir2
>mkdir dir1/a_directory
>ln dir1/a_directroy dir2/directory_link
>cd dir2/directory_link
>cd ..
>pwd
>

This sounds more mysterious than it is.  When a_directory is created,
its parent is dir1, and it stays there.  When directory_link is
created, all that happens is that the directory dir2 gets a new entry
that names the same inode as a_directory.  The a_directory inode is NOT
changed (except that its reference count increases), so its parent is
still dir1.  So,

	pwd == dir1

in any unix I know of.
-- 

 == Mark Warren                      Bull HN Information Systems Inc. ==
 == (508) 294-3171 (FAX 671-3020)    300 Concord Road     MS820A      ==
 == mwarren@granite.cr.bull.com      Billerica, MA 01821              ==