Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!uunet!samsung!zaphod.mps.ohio-state.edu!tut.cis.ohio-state.edu!usenet.ins.cwru.edu!mephisto!prism!bb16
From: bb16@prism.gatech.EDU (Scott Bostater)
Newsgroups: comp.lang.pascal
Subject: Re: Rusty programmer seeks help...
Message-ID: <4222@hydra.gatech.EDU>
Date: 8 Dec 89 06:26:22 GMT
References: <5651@uhccux.uhcc.hawaii.edu>
Reply-To: bb16@prism.gatech.EDU (Scott Bostater)
Distribution: usa
Organization: Georgia Institute of Technology
Lines: 35

In article <5651@uhccux.uhcc.hawaii.edu> webb@uhccux.UUCP (Thomas Webb) writes:
 
[ problem with recursive subroutine stated ]

>program treetmp;
>
>uses DOS;
>
>var
>dirInfo: SearchRec;
>nextDirectory:string;
>
>procedure tree(next:string);
>var
>  dtmp:string;
>begin

   [ guts of procedure deleted to keep rn happy :-( ]

>end;

[ rest of program deleted ]

Your problem is that the variable DirInfor is not local to your recursive 
routine. What's happening is that the second call over-writes the information
in DirInfo that specifies what the filename and pathname are. By making Dirinfo
local to the procedure tree, you keep making copies of Dirinfo on the heap so
that when you return from one level of recursion, the previous data in the
old version of DirInfo is still intact. This method works fine as long as you
have plenty of heap/stack space!
-- 
Scott Bostater      GTRI/RAIL/RAD   (Ga. Tech)
"My soul finds rest in God alone; my salvation comes from Him"  -Ps 62.1
uucp:     ...!{allegra,amd,hplabs,ut-ngp}!gatech!prism!bb16
Internet: bb16@prism.gatech.edu