Winsock2 issues

I hate errors...

Code:

---

$ gcc -o sck sck.o
sck.o:sck.c:(.text+0x45): undefined reference to `WSAStartup@8'
collect2: ld returned 1 exit status

---

Code:

---

#include <stdio.h>
#include <windows.h>
#include <winsock2.h>

int main()
{
        WSADATA wsaData;
       
        if(WSAStartup(MAKEWORD(2, 0), &wsaData) != 0)
        {
                printf("Socket failed to init\n");
                return 0;
        }
        printf("Socket init.\n");
       
        return 0;
}

---

I checked out winsock2.h and WSAStartup() is declared, so I have no idea what's going on. Anyone have any ideas?

You need to link your program against the winsock 2 library (-lws2_32) as well as including the header.

You can do this by making sure your library path includes the folder containing the library (-Lpath/to/lib).

Ahhh, thank you VERY much.

Code:

---

$ gcc -o main main.c -llibws2_32.a -L/lib
main.c: In function `main':
main.c:29: error: `sockaddr_in' undeclared (first use in this function)
main.c:29: error: syntax error before "k"

---

Code:

---

        sockaddr_in k;

---

hrm...

[edit]
Okay, this is really pissing me off. No matter what I do I can't fix this. Adding in the struct definition gives me a redecl error, so I know that it's there, but I don't know why I can't use it!

Show us a few lines around this.

Code:

---

        SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        if(s == INVALID_SOCKET)
        {
                printf("error creating socket: %ld\n", WSAGetLastError());
                WSACleanup();
                return 2;
        }
       
        sockaddr_in k;
        /*k.sin_family = AF_INET;
        k.sin_addr.s_addr = inet_addr("63.240.202.139");
        k.sin_port = htons(6112);

---

I commented everything after to make sure it was just that line...and nothing's wrong with the lines before....

In C, all variables must be declared at the start of the function.

SOCKET s is down there, but I don't get errors from it...grr. I'll try moving that all around.

.....

Code:

---

#include <stdio.h>
#include <winsock2.h>

int main()
{
        WSADATA w;
        SOCKET s;       
        sockaddr_in k;
//......etc

---

Same error -.-

Quote:

---

Originally Posted by CornedBee

In C, all variables must be declared at the start of the function.

---

Actually, I think C99 allows you to mix declarations of variables in with your code. I couldn't find this anywhere in the massive C99 draft, but according to wikepedia it's true.

Code:

---

// sockaddr_in k;
// try this instead:
struct sockaddr_in k;
// or this:
SOCKADDR_IN k; // SOCKADDR_IN is typedef'ed as struct sockaddr_in

---

But no MS compiler supports C99. (GCC does if you set -std=c99. It also supports arbitrary placement of variables if you set -std=gnu89 (the default).)

But I think you're on to something with the struct keyword.

Quote:

---

Originally Posted by CornedBee

But no MS compiler supports C99.

---

I wonder why that is. They've made good strides recently with the compliance of their C++ compiler; I guess they're just not as concerned about the C compiler.

MS doesn't care about C. The core of Windows is in C, but that already can be compiled. Everything else is done in C++ and other higher-level languages.