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<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2>That code's safe from a memory POV, but I wouldn't have
coded it like that personally, because to me, the intentions aren't clear.
I believe that the fact that you had to go and look at the implementation
supports my suggestion of trying to clarify intentions.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2>I haven't used TFindFile (so unsure of all the code), but
personally I would have coded TFindFile so that you would use it along the
lines of:</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2>tf := TFindFile.Create;</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2>try</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2> if tf.SearchForFiles
then
// SearchForFiles does a search and returns a boolean</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2> Memo1.Lines.Assign(tf.FoundFiles);
// where FoundFiles is a TStringList _property_ of TFindFile</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2>finally</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2> tf.Free;</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff size=2>end;</FONT></SPAN></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=854112603-04052007>Neven's free to disagree. I'm not telling people
what to do, I'm just telling you what I find easiest to
follow.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><SPAN class=854112603-04052007><FONT face=Arial color=#0000ff
size=2>C.</FONT></SPAN></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT><BR></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
</DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT size=2><FONT
face=Tahoma><B>From:</B> delphi-bounces@delphi.org.nz
[mailto:delphi-bounces@delphi.org.nz] <B>On Behalf Of </B>John Bird<BR><SPAN
class=854112603-04052007><FONT face=Arial
color=#0000ff> </FONT></SPAN></FONT></FONT></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT size=2><SPAN
class=321173002-04052007><FONT face=Arial color=#0000ff>I have seen an exact
similar case in one of the few external components I use -
TFindFile</FONT></SPAN></FONT></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><SPAN class=321173002-04052007><SPAN class=854112603-04052007><FONT
face=Arial color=#0000ff size=2> </FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=321173002-04052007> </SPAN><FONT size=2><FONT
face=Tahoma>-----Original Message-----<BR><B>From:</B>
delphi-bounces@delphi.org.nz [mailto:delphi-bounces@delphi.org.nz] <B>On Behalf
Of </B>Xander (GMail)</FONT></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">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>
<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><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT
face=Tahoma><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><SPAN
style="FONT-WEIGHT: bold"><SPAN class=854112603-04052007><FONT face=Arial
color=#0000ff> </FONT></SPAN></SPAN></SPAN></FONT></P>
<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><SPAN style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial"><SPAN
class=854112603-04052007> </SPAN></SPAN></DIV>
<DIV><FONT face=Tahoma><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></SPAN></FONT><FONT face=Tahoma><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=854112603-04052007><FONT face=Arial
color=#0000ff> </FONT></SPAN></SPAN></FONT></DIV>
<DIV><FONT face=Tahoma><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></DIV>
<BLOCKQUOTE style="MARGIN-TOP: 5pt; MARGIN-BOTTOM: 5pt; MARGIN-RIGHT: 0cm">
<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
:-)</SPAN></FONT></P></DIV></BLOCKQUOTE></DIV></BLOCKQUOTE></BODY></HTML>