[fpc-devel] POSIX threads and classes

[Helmut Hartl]

>  > fpc 2.0.4, opensuse 10.2, glibc-2.4-31.1

You may try this version of your program 
-----
program Project1;

{$mode objfpc}{$H+}

uses
 UnixType,pthreads;

type

TCondv = class
private
   Cond : UnixType.pthread_cond_t;
   CAttr : UnixType.pthread_condattr_t;
public
  constructor Create;
  destructor Destroy; override;
end;

{TCondv}
constructor TCondv.Create;
begin
  pthread_condattr_init(@CAttr);
  pthread_cond_init(@Cond, @CAttr);
end;


destructor TCondv.Destroy;
begin
  inherited;
  pthread_cond_destroy(@Cond);
  pthread_condattr_destroy(@CAttr);
end;
{TCondv}

var
  obj1 : TCondv;
  obj2 : TCondv;
begin
  obj1 := TCondv.Create;
  obj2 := TCondv.Create;
  obj1.Destroy;
  obj2.Destroy;
end.       
---------------


I had bad experiences with types differently declared in pthreads and
UnixTypes.
Namely the following:

In pthread:

  pthread_cond_t = record
    __c_lock: _pthread_fastlock;
    __c_waiting: _pthread_descr;
  end;

In UnixType: (ptypes.inc)

  pthread_cond_t = record
    __c_lock: _pthread_fastlock;
    __c_waiting: pointer;
    __padding:
array[0..48-1-sizeof(_pthread_fastlock)-sizeof(pointer)-sizeof(clonglong
)] of byte;
    __align: clonglong;
  end;


A call like: i:=pthread_cond_timedwait(@FSignal, @MMutex, at tim);
Fails with the first version (EINVAL), but succedes with the second one.


HTH,
 helmut