C Callbacks

[Noah Roberts]

The functions I am using are not standard, but this is a standard question.

I was under the understanding that you could create a Functor and use it
in place of the function pointer argument to C functions. I haven't
been able to so either I am doing it wrong or I misunderstood.

I am trying to override my signal handler for the SIGCHLD unix signal:

Engine::SIGHandler Engine::sigchld_handler;

Engine::SIGHandler::SIGHandler()
{
signal(SIGCHLD, (void (*)(int))*this);
/*
The above was also tried with (void (*)(int))this which compiles but
blows up with SIGSEGV "in Engine::sigchld_handler ()".
*/
}
void Engine::SIGHandler::operator()(int sig)
{
int status, exit_val;
pid_t pid;

if ((pid = waitpid(-1, &status, WNOHANG)) < 0)
return;

map<pid_t, Engine*>::iterator f = engine_processes.find(pid);
if (f != engine_processes.end())
f->second->handleSigChld(status);
}

So then, the question...

Is what I am attempting possible? How is it done if so?

thanks,
NR

[John Harrison]

"Noah Roberts" <nr******@dontemailme.com> wrote in message
news:3F**************@dontemailme.com...

The functions I am using are not standard, but this is a standard question.
I was under the understanding that you could create a Functor and use it
in place of the function pointer argument to C functions. I haven't
been able to so either I am doing it wrong or I misunderstood.

Sorry but you misunderstood. C functions can only accept function pointers.
I think you are confusing the situation with template classes and template
functions which can accept funciton pointers or functors.

john

[Noah Roberts]

John Harrison wrote:

"Noah Roberts" <nr******@dontemailme.com> wrote in message
news:3F**************@dontemailme.com...

The functions I am using are not standard, but this is a standard
question.

I was under the understanding that you could create a Functor and use it
in place of the function pointer argument to C functions. I haven't
been able to so either I am doing it wrong or I misunderstood.

Sorry but you misunderstood. C functions can only accept function pointers.
I think you are confusing the situation with template classes and template
functions which can accept funciton pointers or functors.

DOH!

thanks.

john