Thread: type casting in C++

Hi

At the moment I'm ill so I'm passing time by doing this so maybe in my current state of mind there's something I'm overlooking.

I have a class which stores the variables needed to construct a simple client socket the address is stored as a C++ string. I keep getting compiler error messages saying it can't convert from string to char * even though I'm casting

Code:

 ServerAdd.sin_addr.s_addr = inet_addr((char *)address);

what am I doing wrong here?
Thank you alll for your time.

I don't think there is an automatic translation available for string to char *. You could use

Code:

address.c_str()

if you just need to make a string into a char array.

--
Mats

Originally Posted by abachler

Code:

LPVOID lpTemp;
 
lpTemp = (LPVOID)address;
 
ServerAdd.sin_addr.s_addr = inet_addr((char *)lpTemp);

you can always recast to/from type void*

Yes, but that will give you the memory-address of the string object address, which doesn't give you the memory-address of the characters in the string (at least, that's far from guaranteed).

--
Mats

oh wait, i reread the original post, seems I missed the fact that he is directly using the string object.

this code will fix the problem -

Code:

 ServerAdd.sin_addr.s_addr = inet_addr((char *)&address);

unless 'address' is already a pointer, in which case my previous post stands.

Thank you for your replies. I think the last post worked but however I threw up another error which maybe or maynot be related. I keep getting

Undefined reference to htons@4

Which probably may or maynot happen if I'd stayed programming on a *nix system.
I thought the "windsock.h" file included all the socket programming headers I needed? #including<netinet/in.h> doesn't resolve this.

MS htons page says that it's winsock2.h ...

--
Mats

No joy. Still throwing the same error. Compiled with Winsock and winsock2.h header files.
BTW thought I should mention that I'm using Dev C++ and I did search for that library file (Ws2_32.lib) on windows but it windows search turned up nothing.

Dev c++ doesnt use the LIB extension, i think they use the .a extension to denote static libraries. I know at least in VS that you have to include the winsock header BEFORE you include windows.h or else it throws all kinds of errors.

Update -

I found the file they use under Dev C++ , its libws2_32.a

include that in the link and that should fix the problem.