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Reading a log file without locking it

Posted on 2004-03-30
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Last Modified: 2010-04-05
Hello,

I have a problem reading a text file.
I'm trying to read a log file, that is often written by an application. I'm tryin to make a sort of real-time-log-viewer.

I tried to open and read it with readln and with readfromfile but when the software reads the log, the writing application fails to write some rows and then the log is incomplete.

Can someone help me??

Thank you very much

Roberto
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Question by:roburobe
7 Comments
 
LVL 17

Expert Comment

by:mokule
ID: 10711784
What procedure do You use for reading?
0
 
LVL 4

Expert Comment

by:k4hvd77
ID: 10711785
hi,
don't know if it Could work, but just an idea!
make a copy from the File, open the copy, do your Operation and than delete it. "copyfile(PChar('SourcePathFileNameHere'),PChar('TargetPath[FileName]Here'),True)"


k4hvd77
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LVL 27

Accepted Solution

by:
kretzschmar earned 500 total points
ID: 10711797
if u use reset()

then set before

filemode := 0;  //open file for read


if you use a tfilestream use

fmOpenread or fmShareDenyNone

just from head

meikl ;-)
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Author Comment

by:roburobe
ID: 10711976
Meikl, thank you very much and sorry for earlier mistake....

Roburobe
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LVL 27

Expert Comment

by:kretzschmar
ID: 10711992
glad to helped you :-))

meikl ;-)
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Author Comment

by:roburobe
ID: 10712876
and what about the .loadfromfile???

Is there a way to execute this method in read-only mode?
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LVL 27

Expert Comment

by:kretzschmar
ID: 10712902
>Is there a way to execute this method in read-only mode?

no, not direct,
you could use something like this

var
  f : TFileStream;
begin
  f := TFileStream.Create('YourLogFileNameHere',fmOpenRead or fmShareDenyNone);
  memo1.lines.loadfromStream(f);
  f.free;
end;


meikl ;-)
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