how to write a wrapper function?

[franco ziade]

I am stuck :(
I am trying to pass the address of a function as an argument to a function
(some OS call to launch a task):

Example:
--------
Declaration of the OS "lunch a Task"
LunchTask(..., * void functionAddress(void), ....)

The function address needs to be passed here, let's say the following

void MyTask::TaskFunction(void);

The compiler refuses it with the error, expecting *void (void) cannot pass
void MyTask::* (void).
I tried to cast but It doesnt accept it :(

I was told i could write a C wrapper function -
Can someone help out on how a wrapper function is used? where is it defined?
how does it pass the C++ function address?

Thanks

[Ben Pfaff]

"franco ziade" <fz****@videotron.ca> writes:

void MyTask::TaskFunction(void);

Your question is outside the domain of comp.lang.c, which discusses
only the standard C programming language, including the standard C
library. This is a remarkably narrow topic compared to what many
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[E. Robert Tisdale]

franco ziade wrote:

I am stuck :(
I am trying to pass the address of a function as an argument to a function
(some OS call to launch a task):

Example:
--------
Declaration of the OS "lunch a Task" LunchTask(..., * void functionAddress(void), ....)

The function address needs to be passed here, let's say the following

void MyTask::TaskFunction(void);
MyTask t; // global object
extern "C" {
void taskFunction(void) {
t.TaskFunction();
}
}
The compiler refuses it with the error,
expecting *void (void) cannot pass void MyTask::* (void).
I tried to cast but It doesnt accept it :(

I was told [that] I could write a C wrapper function -
Can someone help out on how a wrapper function is used?
Where is it defined?
How does it pass the C++ function address?

[Michael Mair]

franco ziade wrote:

I am stuck :(
I am trying to pass the address of a function as an argument to a function
(some OS call to launch a task):

Example:
--------
Declaration of the OS "lunch a Task"
Your OS must be very hospitable.
LunchTask(..., * void functionAddress(void), ....)
A pointer to a function with empty argument list and no returns
looks like that:
void (*functionAddress)(void)
The function address needs to be passed here, let's say the following

void MyTask::TaskFunction(void);

The compiler refuses it with the error, expecting *void (void) cannot pass
void MyTask::* (void).
I tried to cast but It doesnt accept it :(
This is C++. However, try it with function pointers and not some
guess of how they might look. BTW: In C, you do not have to use the
address operator on the function to get its address.

void foo (void);

......
functionAddress = foo;
I was told i could write a C wrapper function -
Can someone help out on how a wrapper function is used? where is it defined?
how does it pass the C++ function address?

Try the above and go on to comp.lang.c++ if it does not work.
Cheers
Michael
--
E-Mail: Mine is an /at/ gmx /dot/ de address.