Wrapping C functions in C++

[Anonymous]

Hi Folks,

I want to wrap the Unix socket library in a C++ class and am having the
following difficulty. I have a method in my C++ class named connect and
within this method I want to call the Unix socket connect function. The
problem is that the compiler complains:

.../common/Socket.h:71: error: no matching function for call to
âSocket::connect(int&, sockaddr*&, int&)â
.../common/Socket.h:37: note: candidates are: void Socket::connect(const
char*, int)

Notice that it is looking within my Socket class for connect(int, sockaddr,
int), but it really should be looking in the C-based socket library. What
I've done as a kludgy fix is to create a forwarding function:

fConnect(int, sockaddr, int) {
connect(int, sockaddr, int);
}

class Socket {
connect() {
fConnect(int, sockaddr, int);
}
}

But I find this to be ugly. Is there a better way to accomplish this,
perhaps my simply specifying which connect I want to call within the class,
instead of having to deal with renaming things?

Thank you.

 

[Martin Steen]

Hi Folks,

I want to wrap the Unix socket library in a C++ class and am having the
following difficulty. I have a method in my C++ class named connect and
within this method I want to call the Unix socket connect function.

try ::connect() to call the global function.

-Martin

 

[Ron Natalie]

class Socket {
connect() {
fConnect(int, sockaddr, int);
}
}

This has nothing to do with connect being a C function.
It has entirely everything to do with names in different
scopes. Inside Socket::connect() the lookup yields
Socket::connect(). If you want the global namespace
connect, all you do is add the scope resolution operator:


connect() {
::connect(int, sockaddr, int);
}

 

[Zara]

Hi Folks,

I want to wrap the Unix socket library in a C++ class and am having the
following difficulty. I have a method in my C++ class named connect and
within this method I want to call the Unix socket connect function.

class Socket {
connect() {
fConnect(int, sockaddr, int);

use instead:
::connect(int,sockaddr,int);

}
}

This tells the compiler tyo look for connect at the global scope.

Once you have corrected all errros that will arise from trying to use
the token "int" as parameter to call a function and some similiar
ones... you will have your connect function working.

Zara

 

[mlimber]

Hi Folks,

I want to wrap the Unix socket library in a C++ class and am having the
following difficulty. I have a method in my C++ class named connect and
within this method I want to call the Unix socket connect function. The
problem is that the compiler complains:

../common/Socket.h:71: error: no matching function for call to
âSocket::connect(int&, sockaddr*&, int&)â
../common/Socket.h:37: note: candidates are: void Socket::connect(const
char*, int)

Notice that it is looking within my Socket class for connect(int, sockaddr,
int), but it really should be looking in the C-based socket library. What
I've done as a kludgy fix is to create a forwarding function:

fConnect(int, sockaddr, int) {
connect(int, sockaddr, int);
}

class Socket {
connect() {
fConnect(int, sockaddr, int);
}
}

But I find this to be ugly. Is there a better way to accomplish this,
perhaps my simply specifying which connect I want to call within the class,
instead of having to deal with renaming things?

Yes, explcitly qualify the socket's connect function as being in the
global namespace:

::connect( someInt, someAddr, someOtherInt );

Cheers! --M