Path: utzoo!attcan!uunet!cs.utexas.edu!rutgers!att!cbnewsh!jgy
From: jgy@cbnewsh.ATT.COM (john.g.young)
Newsgroups: comp.bugs.sys5
Subject: Re: 'ls -n' opens password file for reading
Summary: speaking of ls
Message-ID: <638@cbnewsh.ATT.COM>
Date: 16 May 89 13:31:19 GMT
References: <1326@rivm05.UUCP> <128@softop.UUCP> <1622@auspex.auspex.com> <1245@aplcen.apl.jhu.edu>
Distribution: na
Organization: AT&T Bell Laboratories
Lines: 18

Another problem with 'ls' is with nameless userids.  Try creating
a few files with userids which don't have entries in the password
file.  Use the same userid for each, if your password file is of
a reasonable length you will be treated to a considerable delay
between each line of output as ls parses the entire file for each
output line.

Two possible improvements:
	1) ls currently (svr3) remembers the last uid & gid
	searched for an SUCCESFULLY found in the /etc/(passwd|group)
	file.  This "buffer :)" should be enlarged and also include
	unfound ids.
	
	2) This would elliviate the need for a larger buffer;
	use some kind of database system to speed up access to
	the password file (I belive some BSD systems may do this)
	and/or keep it in a shared memory segment (locked in core).