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From: tchrist@convex.COM (Tom Christiansen)
Newsgroups: comp.lang.perl
Subject: Re: undef of dbm elements?
Message-ID: <1991Jan02.205309.12903@convex.com>
Date: 2 Jan 91 20:53:09 GMT
References: <5073@atexnet.UUCP>
Sender: news@convex.com (news access account)
Reply-To: tchrist@convex.COM (Tom Christiansen)
Organization: CONVEX Software Development, Richardson, TX
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From the keyboard of lawrence@epps.kodak.com:
:The perl man page says "Undef will pobably not do what you expect on ... dbm 
:array values".  
:What exactly _does_ it do?
:Given 
:        dbmopen( %Control, "dbmfilename", 0660 );
:will
:        undef $Control{ "foo" };
:remove the key (and associated value) "foo" from the file "dbmfilename"?
:If not, is there a way to do so?
:Please reply by mail - I will summarize to the net.

I tried to reply but the mail bounced.  You want to use delete, not undef,
to get rid of it entirely.  Otherwise you'll have a key whose value is
undef, as opposed to not having the key at all.

--tom
--
Tom Christiansen		tchrist@convex.com	convex!tchrist
"With a kernel dive, all things are possible, but it sure makes it hard
 to look at yourself in the mirror the next morning."  -me