How to call a multithreaded UDT Sub???

[mrminecrafttnt]

Code: Select all

type sec_integer
    dim as integer value
    declare sub mt_watchdog
    declare constructor 
end type

sub sec_integer.mt_watchdog
    do
        print "IT WORKS!"
    loop until inkey <> ""
end sub

constructor sec_integer

     threadcall sec_integer.mt_watchdog
end constructor

sleep

        

Ouput:

FBIDETEMP.bas(15) error 6: Expected '(' in 'threadcall sec_integer.mt_watchdog'

[SARG]

By adding () at the end of name.... And no need "sec_integer"

Code: Select all

threadcall mt_watchdog () 

seems to be enough.

When running libffi-6.dll is necessary otherwise error message.

[mrminecrafttnt]

Works fine, thanks! But why crashes this simple code???

Code: Select all

type sec_integer
    dim as integer update
  
    declare sub mt_watchdog

    declare constructor
end type

    constructor sec_integer
         threadcall mt_watchdog()
    end constructor
        
    
    
    sub sec_integer.mt_watchdog
print 1
        do
            print 2
            sleep 1
            print 3
            if update = 1 then
                print 4
                do
                    print 5
                    sleep 10
                    print 6
                loop until update = 0
                print 7
            end if
            print 8

        loop until update = -1
        print 9
    end sub
    print 10
    dim as sec_integer test
    print 11
    sleep
    
    

-exx = no output???

[fxm]

The SARG solution is not safe, and can only works if the thread accesses to static fields only.

If the thread must access to non static member fields, you must add a static wrapper.
In addition, as cited in the documentation, the ThreadCall working is not presently guaranteed when parameters must be passed (the object instance).
Instead use ThreadCreate.

Simple example:

Code: Select all

type sec_integer
    dim as integer value
    declare sub mt_watchdog
    declare static sub mt_watchdog_launcher (byval p as any ptr)

    declare constructor
end type

    constructor sec_integer
        threadcreate(@sec_integer.mt_watchdog_launcher, @this)
    end constructor
       
    sub sec_integer.mt_watchdog ()
        do
            print "IT WORKS!", value
            sleep 1
        loop until inkey <> ""
    end sub
    
    static sub sec_integer.mt_watchdog_launcher (byval p as any ptr)
        cptr(sec_integer ptr, p)->mt_watchdog()
    end sub

dim as sec_integer test
test.value = 1234
sleep

[mrminecrafttnt]

This is what i need thanks :)

[Tourist Trap]

This is what i need thanks :)

You have a discussion leading to fxm's proposal here below ( of course you'll say, it's all fxm solution there ;) ):
viewtopic.php?f=2&t=23898&p=211070&hili ... 2A#p211070

[fxm]

The behavior of the unsafe solution of SARG (inducing access restricted to static fields only), is very comparable to the one of the member procedure call on a null pointer.

[SARG]

My reply was just about the compile error (first post). So that's not really MY unsafe solution.... ;-)

[fxm]

Please excuse me.

But at the same time, I think you have found what looks like a compiler bug that should also issue an error message on that other proposed syntax:

Code: Select all

Type UDT
  Dim As Integer value
  Declare Sub thread ()
  Declare Sub thread_start ()
end type

Sub UDT.thread ()
  Do
      Print "IT WORKS!"  ', value  '' program crashes when accessing to value
  Loop Until Inkey <> ""
End Sub

Sub UDT.thread_start ()
'  Threadcall This.thread()  '' compiler error => OK
  Threadcall UDT.thread()   '' no compiler error => NOK
  Threadcall thread()       '' no compiler error => NOK
End Sub

Dim As UDT u
u.thread_start

Sleep

[SARG]

Please excuse me.

No problem.
To be honnest no real running test as libffi-6.dll was missing.

But at the same time, I think you have found what looks like a compiler bug that should also issue an error message on that other proposed syntax:

Find shared with mrminecrafttnt ;-)

[Tourist Trap]

I think you have found what looks like a compiler bug

Unfortunately no more dkl in sight for a magic instant fix...

[fxm]

Compiler bug (see my above code at viewtopic.php?p=235337#p235337):
From inside a non static member procedure, ThreadCall allows to start as a thread a non static member Sub (without any parameters), which crashes only if attempting to access a non static member field (same execution behavior than calling a non static member procedure on a null pointer).

[fxm]

Bug report filled:
#861 From inside a non static member procedure, ThreadCall allows to start as a thread a non static member Sub()