From artendulkar at yahoo.com  Fri Jun 10 09:45:21 2005
From: artendulkar at yahoo.com (Abhijit Tendulkar)
Date: Fri, 10 Jun 2005 02:45:21 -0700 (PDT)
Subject: Problem in type conversion in pthread_create
Message-ID: <20050610094521.29158.qmail@web53308.mail.yahoo.com>

Hello,

I'm new to this list, this is my first post.

I'm getting the type conversion error in my program.
I tried it in following way.

This is the function in which threads are to be
created:

void MonteCarlo :: generateEnrmap(vector<string> vstr,
int ns, float svdw, float er)
{
        arg ar, *arptr;
        //void *arptr;
        void *ptr;
        pthread_t id;
        int mid = _pgrmap.size() / 2;
        ar.vstr = vstr;
        ar.ns = ns;
        ar.svdw = svdw;
        ar.er = er;
        ar.mid = mid;
        //arptr = &ar;
        ptr = &ar; //arptr;
        if( 0 == pthread_create(&id, NULL,
generateEnrmap1, ptr) ) //Line No. 416
                cout<<"First thread created.\n";
        if( 0 == pthread_create(&id, NULL,
generateEnrmap2, ptr) ) //Line No. 418
                cout<<"Second thread created.\n";
        pthread_exit(NULL);
}

These are prototypes of two functions used in threads.
void * MonteCarlo :: generateEnrmap1(void *ptr)
void * MonteCarlo :: generateEnrmap2(void *ptr)

The only error I'm getting is as follows.

-bash-2.05b$ make
g++  -c -lpthread source/MonteCarlo.cc -Iheader
source/MonteCarlo.cc: In member function `void
   MonteCarlo::generateEnrmap(std::vector<std::string,
   std::allocator<std::string> >, int, float, float)':
source/MonteCarlo.cc:416: error: argument of type
`void*(MonteCarlo::)(void*)'
   does not match `void*(*)(void*)'
source/MonteCarlo.cc:418: error: argument of type
`void*(MonteCarlo::)(void*)'
   does not match `void*(*)(void*)'
make: *** [MonteCarlo.o] Error 1
-bash-2.05b$

Can anybody please help me in removing this error?
why this error message is showing one more * in
bracket?

Waiting for reply.

Thanks & regards.

Abhijit


		
__________________________________ 
Discover Yahoo! 
Stay in touch with email, IM, photo sharing and more. Check it out! 
http://discover.yahoo.com/stayintouch.html


From TEREKHOV at de.ibm.com  Fri Jun 10 13:42:14 2005
From: TEREKHOV at de.ibm.com (Alexander Terekhov)
Date: Fri, 10 Jun 2005 15:42:14 +0200
Subject: [c++-pthreads] Problem in type conversion in pthread_create
In-Reply-To: <20050610094521.29158.qmail@web53308.mail.yahoo.com>
Message-ID: <OF88BE4021.9D205B02-ONC125701C.0049B94B-C125701C.004B1746@de.ibm.com>


> I'm new to this list

This list is dead (http://tinyurl.com/dz23x is sorta new
incarnation), and judging from your question, you'll be
better served at comp.programming.threads. Search the
archives first.

regards,
alexander.



From Stephen.Clamage at Sun.COM  Fri Jun 10 15:32:29 2005
From: Stephen.Clamage at Sun.COM (Steve Clamage)
Date: Fri, 10 Jun 2005 08:32:29 -0700
Subject: [c++-pthreads] Problem in type conversion in pthread_create
In-Reply-To: <20050610094521.29158.qmail@web53308.mail.yahoo.com>
References: <20050610094521.29158.qmail@web53308.mail.yahoo.com>
Message-ID: <42A9B28D.4020803@sun.com>

Function pthread_create is a C function, and needs to be passed the
address of an ordinary function with C linkage.

You are attempting to pass it the address of what appears to be a class
member function. The address of a class member function is not an
ordinary pointer-to-function, and is incompatible with
pointer-to-function.  In any event, the function you are passing has C++
linkage.

You need to create global functions with C linkage for passing to
pthread_create. Those function can be written in C++, and can use C++
features.

---
Steve Clamage, stephen.clamage at sun.com

Abhijit Tendulkar wrote:
> Hello,
> 
> I'm new to this list, this is my first post.
> 
> I'm getting the type conversion error in my program.
> I tried it in following way.
> 
> This is the function in which threads are to be
> created:
> 
> void MonteCarlo :: generateEnrmap(vector<string> vstr,
> int ns, float svdw, float er)
> {
>         arg ar, *arptr;
>         //void *arptr;
>         void *ptr;
>         pthread_t id;
>         int mid = _pgrmap.size() / 2;
>         ar.vstr = vstr;
>         ar.ns = ns;
>         ar.svdw = svdw;
>         ar.er = er;
>         ar.mid = mid;
>         //arptr = &ar;
>         ptr = &ar; //arptr;
>         if( 0 == pthread_create(&id, NULL,
> generateEnrmap1, ptr) ) //Line No. 416
>                 cout<<"First thread created.\n";
>         if( 0 == pthread_create(&id, NULL,
> generateEnrmap2, ptr) ) //Line No. 418
>                 cout<<"Second thread created.\n";
>         pthread_exit(NULL);
> }
> 
> These are prototypes of two functions used in threads.
> void * MonteCarlo :: generateEnrmap1(void *ptr)
> void * MonteCarlo :: generateEnrmap2(void *ptr)
> 
> The only error I'm getting is as follows.
> 
> -bash-2.05b$ make
> g++  -c -lpthread source/MonteCarlo.cc -Iheader
> source/MonteCarlo.cc: In member function `void
>    MonteCarlo::generateEnrmap(std::vector<std::string,
>    std::allocator<std::string> >, int, float, float)':
> source/MonteCarlo.cc:416: error: argument of type
> `void*(MonteCarlo::)(void*)'
>    does not match `void*(*)(void*)'
> source/MonteCarlo.cc:418: error: argument of type
> `void*(MonteCarlo::)(void*)'
>    does not match `void*(*)(void*)'
> make: *** [MonteCarlo.o] Error 1
> -bash-2.05b$
> 
> Can anybody please help me in removing this error?
> why this error message is showing one more * in
> bracket?
> 
> Waiting for reply.
> 
> Thanks & regards.
> 
> Abhijit
> 
> 
> 		
> __________________________________ 
> Discover Yahoo! 
> Stay in touch with email, IM, photo sharing and more. Check it out! 
> http://discover.yahoo.com/stayintouch.html