Thread - linux - raspbian-buster

[Mi-Ki]

Hello.
How to make thead?
Everything I try and works under windows doesn't work in linux.

Project projectl raised exception class 'RunError(232)'.
At address 6B
https://i.postimg.cc/RV0MK05y/error.png

Function thead also does not work in linux.

Code: Pascal  [Select][+][-]

1. var
2.   Form1: TForm1;
3.   thh: THandle;
4.  
5. implementation
6.  
7. {$R *.lfm}
8.  
9. { TForm1 }
10. Function OtevriThread(Param: Pointer): Longint;
11. begin
12.   beep;
13.   EndThread (thh);
14. end;
15.  
16. procedure TForm1.Button1Click(Sender: TObject);
17. var
18.   thid: Cardinal;
19. begin
20.   thh:=BeginThread(nil,0,@OtevriThread,nil,0,thid);
21. end;                        

Linux error 'RunError(232)'.
It works in windows.

[Xor-el]

Hi, did you add the unit cthreads to the uses clause?

https://www.freepascal.org/docs-html/current/rtl/cthreads/index.html

[Mi-Ki]

@Xor-el
When I add cthreads to uses then error.
Project projectl raised exception class 'RunError(211)'.

[avra]

When I add cthreads to uses then error.

Did you add it as a first unit in main project file? As shown:

Code: Pascal  [Select][+][-]

1. uses
2.   {$ifdef unix}cthreads{$endif},
3.    classes, sysutils;

[rvk]

Why are you calling endthread with parameter thh?

It is
procedure EndThread(ExitCode : DWord);

So you give it an exitcode (i.e. 0 or any other if it's an error).
Calling it with tth will pass a thread pointer as exitcode which leads to unexpected results.
 
So just use
EndThread(0);

[Mi-Ki]

Code: Pascal  [Select][+][-]

1. uses
2.   {$ifdef unix}cthreads{$endif},
3.   Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls;  
4.  
5. Function OpenThread(Param: Pointer): Longint;
6. begin
7.   beep;
8.   EndThread(0);
9. end;
10.  
11. procedure TForm1.Button1Click(Sender: TObject);
12. var
13.  thh: THandle;
14.  thid: Cardinal;
15. begin
16.  thh:=BeginThread(nil,0,@OpenThread,nil,0,thid);
17. end;

                               
Project projectl raised exception class 'RunError(211)'.

[devEric69]

Seriously, I think you should read how to use the Lazarus TThread class ( and it will save you time for the future ), as well as examples of synchronous or asynchronous inter-threads use.

My two cents.

[Thaddy]

Project projectl raised exception class 'RunError(211)'.

That seems highly unlikely, because 211 is an abstract error and you are not using classes. RunError( 232) is more likely: use cthreads unit.

Try the class method TThread.ExecuteInThread:

Code: Pascal  [Select][+][-]

1. {$mode delphi}{$H+}
2. uses cthreads,classes;
3.  
4. procedure Aproc(data:pointer);
5. begin
6.   writeln('written from thread');
7. end;
8. begin
9.   TThread.ExecuteInThread(@AProc); // class method, no instance necessary
10. end.

Tested on Raspbian buster.

[avra]

Project projectl raised exception class 'RunError(211)'.

You use cthreads in unit where your form is. That is not main project LPR file.

[Thaddy]

You use cthreads in unit where your form is. That is not main project LPR file.

Yes but that is runerror(232), NOT 211 which is an abstract error.
https://freepascal.org/docs-html/current/user/userap4.html#x190-197000D

I think that was a typo.

[munair]

You use cthreads in unit where your form is. That is not main project LPR file.

Indeed. In a recent project I implemented a thread and it compiles and runs fine on both Windows 32/64 and Linux 64. In the lpr file the following uses clause is included:

Code: Pascal  [Select][+][-]

1. uses
2.   {$IFDEF UNIX}{$IFDEF UseCThreads}
3.   cthreads,
4.   {$ENDIF}{$ENDIF}
5.   Interfaces, // this includes the LCL widgetset
6.   Forms, umain, LazSerialPort
7.   { you can add units after this };

As you can see it is placed BEFORE the others. Then in the main form's unit a thread class is defined:

Code: Pascal  [Select][+][-]

1. unit umain;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, Forms, Controls, Graphics, Dialogs, StdCtrls, ExtCtrls,
9.   Math, LazSerial, DateUtils, FileUtil, LazSysUtils;
10.  
11. type
12.   TReadDataThread = class(TThread)
13.   private
14.     procedure UpdateList;
15.   protected
16.     procedure Execute; override;
17.   public
18.     constructor Create(CreateSuspended: boolean);
19.   end;
20.  
21.   { TForm1 }
22. ...

Works like a charm, but you have to read some documentation  in order to implement it properly. Especially interface related stuff should be done separately (in my example this is done by calling Synchronize(@UpdateList); from the Execute procedure.