🚀 go-pugleaf

"DavideP" <no.spam@here.plz> wrote in message
news:45b793fe@newsgroups.borland.com...

> by clicking several times on it I've found multiple istances of
Notepad opened...

As you should be.  That is how WinExec() works - it creates a new
process each time it is called.

> How can I avoid this feature?

You can't.  Notepad is not designed for that, and there is nothing
WinExec() (or CreateProcess(), for that matter) can do about it.

The called program, not the calling program, controls how the file is
loaded.  If the called program does not want to run multiple
instances, then it has to control that on its own.  The calling
program has no say in that matter.

> I need only one instance of notepad with my logfile.

Then I suggest you not use Notepad at all.  Display the log in your
own UI, such as in a TMemo or TRichEdit control..  Then you have full
control over it.  If you must use an external program, then write your
own.  Then it can avoid multiple instances of itself.  It is a very
common feature to implement, so there are plenty of examples floating
around to look at.


Gambit

DavideP wrote:
> Hi everyone,
> I've a little question.
>
> I need to display a logfile of a program of mine, so I use:
> WinExec('Notepad.exe C:\Temp\MyFile.txt', SW_SHOWDEFAULT);
> on a OnClick event of a button.
>
> It works well, but... by clicking several times on it I've found 
> multiple istances of Notepad opened...
> How can I avoid this feature?
> I need only one instance of notepad with my logfile.
>
> Many thanks for the help.
>
> Davide
>   
Just set a flag in your program... if WinExec has already been called, 
ignore
the second pressure on that button.
You can reset that flag when the Notepad process terminates.

Alberto

Alberto <dibene@usa.net> wrote:

>Just set a flag in your program... if WinExec has already been called, 
>ignore
>the second pressure on that button.
>You can reset that flag when the Notepad process terminates.

You could use a single handle onto the process. If the handle is already
non-null, then it's running (or you've not yet checked its termination
condition). If null, you've either never run it, or you've seen it
terminate already and reset the handle to null.

On the other hand, though this would technically work, it's unlikely to
provide the probable required functionality of loading the latest log
state. For this, a simple window with a simple edit control on it would
be better.

Alan Bellingham
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