Is there any problem with sending function pointers through in a
variable argument list? I have a function like the following:
typedef (*ptr2FuncType1 )( int );
typedef (*ptr2FuncType2 )( double );
void SomeClass::DoSo mething( unsigned int num_something, unsigned long
num_something_e lse, ptr2FuncType1 handler_one, ... )
The functions I am passing in are in a different cpp file, but they
are not memeber functions of any class.
Where the ... represents the function pointers which I am sending to
the function. Inside that function I initialize a member array that
contains those pointers to functions. So I use va_start( arglist,
handler_one ) to start the arg list.
Then to get to each function pointer I use
m_pFuncArray[i] = va_arg( arglist, ptr2FunctionTyp e2 );
etc....
When I try and call the functions later in another class function, I
get a program crash from memory error. The thing I am thinking is that
the program needs to code segment as well as the address of the
function to be able to call it. Is there anything special I need to do
with variable arguments to get functions pointers to work correctly?
Thanks!
Alex Earl
1  6738 
"Alex" <sl*********@ho tmail.com> wrote in message news:b7******** *************** ***@posting.goo gle.com...
Then to get to each function pointer I use
m_pFuncArray[i] = va_arg( arglist, ptr2FunctionTyp e2 );
Provided that the argument is really of type ptr2FunctionTyp e2, this should be ok.
Are you sure you haven't screwed up the types. There is NO checking provided
by va_arg. Also make sure you have extracted the prior args in the list correctly
as once you screw one up the ohters can be hosed.
When I try and call the functions later in another class function, I
get a program crash from memory error. The thing I am thinking is that
the program needs to code segment as well as the address of the
function to be able to call it. Is there anything special I need to do
with variable arguments to get functions pointers to work correctly?
The compier is supposed to take all that into account when encoding the
pointer. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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