[fpc-pascal] Linux library access violation

[Chris]

I get an "Access violation" when I call a function from a C library.
Not sure if I can explain well enough, so I will just post the code:

The C library:
#include <stdio.h>
#include <string.h>

int testreturn(const char *thename, char *rcity, char *rstate)
{

    memcpy (rcity,"Boston",7);
    memcpy (rstate,"Massachusetts",14);

return strlen(thename);
}

The C library is compiled and named libTester.so

The code I call to the function from is:

unit Unit1;

{$mode objfpc}{$H+}

interface

uses
 Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, 
StdCtrls,
 Buttons, StrUtils;

type

 { TForm1 }

 TForm1 = class(TForm)
   Button1: TButton;
   Edit1: TEdit;
   Edit2: TEdit;
   Edit3: TEdit;
   procedure Button1Click(Sender: TObject);
 private
   { private declarations }
 public
   { public declarations }
 end;

var
 Form1: TForm1;
 function testreturn(thename:pchar;rcity:pchar;rstate:pchar):integer; 
stdcall; external 'libTester';

implementation

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);
var
   rlines : array[0..1] of string;
   retint : integer;
   ganame : string;
begin
 ganame := Trim(Edit1.Text);
 rlines[0] := StringOfChar('0', 80);
 rlines[1] := StringOfChar('0', 80);
 retint := testreturn(pchar(ganame), pchar(rlines[0]), pchar(rlines[1]));
 Edit2.Text := AnsiLeftStr(rlines[0], pos(Chr(0), rlines[0]) - 1);
 Edit3.Text := AnsiLeftStr(rlines[1], pos(Chr(0), rlines[1]) - 1);
 Form1.Caption := 'Name Length: ' + inttostr(retint);
end;

initialization
 {$I unit1.lrs}

end.

It works well but, I get a message box that pops up that says "Access 
violation" press OK to continue and risk possible data corruption or 
Cancel to exit.

I click OK and its fine. It returns everything correctly. That message 
box is a pain though. I tried:
try
 retint := testreturn(pchar(ganame), pchar(rlines[0]), pchar(rlines[1]));
except
//do something
end;

But the program just quits.

Any help?

Thanks


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