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<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>I have
seen an exact similar case in one of the few external components I use -
TFindFile</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>which
has code like:</FONT></SPAN></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2>s:TStringlist is a private variable in the FindFiles
unit,</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2>function TFindFile.SearchForFiles:
TStringList;<BR>begin<BR> s.Clear;<BR> try<BR>
FileSearch(Path);<BR> finally<BR> Result := s;<BR>
end;<BR>end;<BR></FONT></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>the
only reference to s in the FileSearch function is</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2> s.Add(inPath +
Rec.Name);<BR></FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>The
component also has:</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2>constructor TFindFile.Create(AOwner: TComponent);<BR>begin<BR>
inherited Create(AOwner);<BR> Path :=
IncludeTrailingBackslash(GetCurrentDir); <BR> FileMask := '*.*';<BR>
FileAttr := [ffaAnyFile];<BR> s :=
TStringList.Create;<BR>end;</FONT></SPAN></DIV>
<DIV> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2>destructor TFindFile.Destroy;<BR>begin<BR> s.Free;<BR>
inherited Destroy;<BR>end;<BR></FONT></SPAN></DIV></DIV></FONT></SPAN>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>I call
it from my program with code like:</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>
strlist:TStringList;</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2>and</DIV>
<DIV><BR></DIV></FONT></SPAN>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>
strlist:=FindFile1.SearchforFiles;</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>That
is I do no creating or freeing of the strlist myself - the component does all of
the housework is my understanding. Thats one of the reasons I use it, as
it encapsulates a few fiddly things like this.</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>Is
this correct use or is this creating memory leaks? I found errors if I
tried to create or free the strlist myself - and was advised that effectively
the component was doing this and I didn't need to.</FONT></SPAN></DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=321173002-04052007><FONT face=Arial color=#0000ff size=2>[This
is a utility I have for recursive folder searches of source files for a matching
string displaying matches in a stringgrid - a sort of visual Grep - would be
happy to share it if anyone can point out any errors or
improvements] </FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2>F<SPAN
class=321173002-04052007>rom the Help</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=321173002-04052007></SPAN></FONT></FONT></FONT></SPAN> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007>"TStringList.Clear:</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007>Deletes all the strings from the
list.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007>procedure Clear; override;</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007>Description</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=321173002-04052007>Call
clear to empty the list of strings. All references to associated objects are
also removed. However, the objects themselves are not
freed."</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=321173002-04052007></SPAN></FONT> </DIV>
<DIV class=Section1>
<P class=MsoAutoSig align=left>John<SPAN class=321173002-04052007><FONT
face=Arial color=#0000ff size=2> </FONT></SPAN></P>
<P class=MsoAutoSig align=left><SPAN class=321173002-04052007> </SPAN><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B>
delphi-bounces@delphi.org.nz [mailto:delphi-bounces@delphi.org.nz] <B>On Behalf
Of </B>Xander (GMail)<BR><B>Sent:</B> Friday, 4 May 2007 2:02 p.m.<BR><B>To:</B>
'NZ Borland Developers Group - Delphi List'<BR><B>Subject:</B> RE: [DUG] Dumb
Friday Question<BR><BR></P></FONT></DIV>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px">
<DIV class=Section1>
<P class=MsoNormal><FONT face=Verdana color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Verdana">Jeremy,<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Verdana color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Verdana"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Verdana color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Verdana">If the function
returns a TStringList then it should be the responsibility of the caller of
that function to FREE the returned TStringList after it has finished using it.
You cannot free it inside the function.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Verdana color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Verdana"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Verdana color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Verdana">Regards<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Verdana color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Verdana"><o:p> </o:p></SPAN></FONT></P>
<DIV>
<DIV class=MsoNormal style="TEXT-ALIGN: center" align=center><FONT
face="Times New Roman" size=3><SPAN style="FONT-SIZE: 12pt">
<HR tabIndex=-1 align=center width="100%" SIZE=2>
</SPAN></FONT></DIV>
<P class=MsoNormal><B><FONT face=Tahoma size=2><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT
face=Tahoma size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">
delphi-bounces@delphi.org.nz [mailto:delphi-bounces@delphi.org.nz] <B><SPAN
style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B>Leigh Wanstead<BR><B><SPAN
style="FONT-WEIGHT: bold">Sent:</SPAN></B> Friday, May 04, 2007 1:55
PM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> vss@vss.co.nz;
<st1:PersonName w:st="on">NZ Borland Developers Group - Delphi
List</st1:PersonName><BR><B><SPAN
style="FONT-WEIGHT: bold">Subject:</SPAN></B> RE: [DUG] Dumb Friday
Question</SPAN></FONT><o:p></o:p></P></DIV>
<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"><o:p> </o:p></SPAN></FONT></P>
<DIV>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">Hi
Jeremy,</SPAN></FONT><o:p></o:p></P></DIV>
<DIV>
<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">I think you need this
one <A
href="http://v.mahon.free.fr/pro/freeware/memcheck">http://v.mahon.free.fr/pro/freeware/memcheck</A></SPAN></FONT><o:p></o:p></P></DIV>
<DIV>
<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">;-)</SPAN></FONT><o:p></o:p></P></DIV>
<DIV>
<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">Regards</SPAN></FONT><o:p></o:p></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">Leigh</SPAN></FONT><o:p></o:p></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial"><A
href="http://www.smootharm.com">www.smootharm.com</A></SPAN></FONT><o:p></o:p></P></DIV>
<BLOCKQUOTE style="MARGIN-TOP: 5pt; MARGIN-BOTTOM: 5pt; MARGIN-RIGHT: 0cm">
<P class=MsoNormal style="MARGIN-BOTTOM: 12pt"><FONT face=Tahoma
size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">-----Original
Message-----<BR><B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B>
delphi-bounces@delphi.org.nz [mailto:delphi-bounces@delphi.org.nz]<B><SPAN
style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B>Jeremy Coulter<BR><B><SPAN
style="FONT-WEIGHT: bold">Sent:</SPAN></B> Friday, 4 May 2007 1:28
p.m.<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B>
delphi@delphi.org.nz<BR><B><SPAN
style="FONT-WEIGHT: bold">Subject:</SPAN></B> [DUG] Dumb Friday
Question</SPAN></FONT><o:p></o:p></P>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">Hi All. This is a question that
might be infulenced by some serious lack of sleep
:-)<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">I have a funtion. Its return
result is a TStringlist.<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">In my code I create
a TStringlist then add my values to it, then pass this to the RESULT
varaible for the function.<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">Now, this is prob. an
obvious answer than I prob. do actually know, but if I
got:-<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">sResult :=
TStringList.create;<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">sResult.add('blah');<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">Result:=sResult;<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">Then if I free sResult, then I
loss the values I added, and the result is empty as you would
expect.<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">But the issue I have is, so if
I DONT free sResults, what happens to it? Surley it stays in memory,a dn I
would end up with a memory leack after repeaditive calls. Is that right? Or
is because the variable is function specific its free by default
etc?<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">Its a basic question I
know....but the more I thought about it the more uncertain I became....I
really need some sleep so that prob. the real probelm
:-)<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">Jeremy<o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal><FONT face=Tahoma size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> <o:p></o:p></SPAN></FONT></P></DIV></BLOCKQUOTE></DIV><BR><BR>__________
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