Simple Winsock Code using DevCPP

I just need a little help before getting deep into network programming.. I am attempting to make what is nothing more than a "hello world" of winsock api by playing with a couple of functions.

The first problem is that I cannot get my code to compile using either the <winsock.h> or <winsock2.h> header. I have attached a pic of all compiler errors. I have browsed the, "include" folder located in DevCPP and have located both the winsock.h and winsock2.h header files. Compiler options are at default settings and provide paths to the devcpp 'include' folder.

There may be additional errors.. I am kinda new at winsock api and may have made a few syntactical mistakes.

Please help if ye' can.

Code:

---

#include<iostream>
#include<winsock2.h>

using namespace std;

int main()
{
    WSADATA wsd;
    WSAPROTOCOL_INFO *proto;
    LPDWORD bufferlength = NULL;
   
    WSAStartup(MAKEWORD(2,2), &wsd);
   
    cout << "\n\nUsing winsock version " << wsd.wVersion;
   
    //This call will fail, but will return the correct buffer size
    WSAEnumProtocols(NULL, NULL, bufferlength);
   
    //Allocate the correct buffer size of WSAPROTOCOL_INFO structures
    proto = new WSAPROTOCOL_INFO[*bufferlength];
   
    //Populate an array of system protocols
    WSAEnumProtocols(NULL, proto, bufferlength);
   
    //Step through the array and view some system supported protocol information
    for(int i=0; i<*bufferlength; i++)
    {
      cout << "\n\n\nVersion:    " << proto[i].iVersion;
      cout << "\nAddress Family: " << proto[i].iAddressFamily;
      cout << "\nMax Sockets:    " << proto[i].iMaxSockAddr;
      cout << "\nMin Sockets:    " << proto[i].iMinSockAddr;
      cout << "\nProtocol:      " << proto[i].szProtocol;
    } 
   
    WSACleanup();
   
    return 0;
}

---

Those are linker errors. You must link to the winsock library.
http://cboard.cprogramming.com/showthread.php?t=54914

I have located and added the libwsock32.a path in my library settings.. but I still get the same linker errors at compile time. What am I missing/overlooking?

It could be libws2_32.a

I finally got winsock code to compile by compiling it as a windows project.. as opposed to c++ source.

I successfully added the llibws2_32.a by going to Project-> Project Options -> parameters, but after compilation execution is terminated.. why???

Code:

---

#include<iostream>
#include<winsock2.h>

using namespace std;

int main()
{
    WSADATA wsd;
    WSAPROTOCOL_INFO *proto;
    LPDWORD bufferlength = 0;
   
    if(WSAStartup(MAKEWORD(2,2), &wsd) != 0)
   
      cout << "\n\aWSAStartup failed.";
     
    else
   
      cout << "\n\nUsing winsock version " << wsd.wVersion;
    /*
    //This call will fail, but will return the correct buffer size
    WSAEnumProtocols(NULL, NULL, bufferlength);
   
    //Allocate the correct buffer size of WSAPROTOCOL_INFO structures
    proto = new WSAPROTOCOL_INFO[*bufferlength];
   
    //Populate an array of system protocols
    WSAEnumProtocols(NULL, proto, bufferlength);
   
    //Step through the array and view some system supported protocol information
    for(int i=0; i<*bufferlength; i++)
    {
      cout << "\n\n\nVersion:    " << proto[i].iVersion;
      cout << "\nAddress Family: " << proto[i].iAddressFamily;
      cout << "\nMax Sockets:    " << proto[i].iMaxSockAddr;
      cout << "\nMin Sockets:    " << proto[i].iMinSockAddr;
      cout << "\nProtocol:      " << proto[i].szProtocol;
    } 
    */
    cout << "Press [ENTER] to continue..."; 
    cin.get();
   
    WSACleanup();
   
    return 0;
}

---

compiler log:

Code:

---

Compiler: Default compiler
Building Makefile: "F:\Dev-Cpp\Makefile.win"
Executing  make...
make.exe -f "F:\Dev-Cpp\Makefile.win" all
make.exe: Nothing to be done for `all'.

Execution terminated
Compilation successful

---

> LPDWORD bufferlength = 0;
When things say they want a pointer to something, it usually means you need a 'something' then you have &something when you call it.

Simply declaring a pointer-to-something just to make the compiler happy isn't the right thing to do, you have to look at what the parameter is being used for and declare accordingly.

Say

Code:

---

    DWORD bufferlength = 0;

    //This call will fail, but will return the correct buffer size
    WSAEnumProtocols(NULL, NULL, &bufferlength);
   
    //Allocate the currect buffer size of WSAPROTOCOL_INFO structures
    proto = new WSAPROTOCOL_INFO[bufferlength];
   
    //Populate an array of system protocols
    WSAEnumProtocols(NULL, proto, bufferlength);
   
    //Step through the array and view some system supported protocol information
    for(int i=0; i<bufferlength; i++)
    {
      cout << "\n\n\nVersion:    " << proto[i].iVersion;
      cout << "\nAddress Family: " << proto[i].iAddressFamily;
      cout << "\nMax Sockets:    " << proto[i].iMaxSockAddr;
      cout << "\nMin Sockets:    " << proto[i].iMinSockAddr;
      cout << "\nProtocol:      " << proto[i].szProtocol;
    }

---

Quote:

---

lib/libws2_32.a

---

Change it to -lws2_32, otherwise the path won't work if you copy/cut your files to somewhere else.

I tried all this stuff.. nothing is working. Can anyone else get this code to compile?

The 'lib' and '.a' are assumed.
So it's just ws2_32

Like so (see image)

That did the trick.. :)
thanks

Can anyone give me any clues as to why this code gives winsock version 514 and a buffer size of 9672 ??

Code:

---

#include<iostream>
#include<winsock2.h>

using namespace std;

int main()
{
    WSADATA wsd;
    WSAPROTOCOL_INFO *proto;
    DWORD bufferlength = 0;
   
    if(WSAStartup(MAKEWORD(2,2), &wsd) != 0)
   
      cout << "\n\aWSAStartup failed...";
     
    else   
   
      cout << "\n\nUsing winsock version " << wsd.wVersion;
   
    //This call will fail, but will return the correct buffer size
    WSAEnumProtocols(NULL, NULL, &bufferlength;
   
    cout << "\n\nThere are " << buffersize << " protocols.";
   
    //Allocate the currect buffer size of WSAPROTOCOL_INFO structures
    proto = new WSAPROTOCOL_INFO[bufferlength];
   
    //Populate an array of system protocols
    WSAEnumProtocols(NULL, proto, &bufferlength);
   
    //Step through the array and view some system supported protocol information
    //I had to use a loop size of 26 because 'buffersize' was huge
    for(int i=0; i<26; i++)
    {
      cout << "\n\n\nProtocol #"  << i+1;
      cout << "\nVersion:        " << proto[i].iVersion;
      cout << "\nAddress Family: " << proto[i].iAddressFamily;
      cout << "\nMax Sockets:    " << proto[i].iMaxSockAddr;
      cout << "\nMin Sockets:    " << proto[i].iMinSockAddr;
      cout << "\nProtocol:      " << proto[i].szProtocol;
    } 
   
    cout << "\nPress [ENTER] to continue...";
    cin.get();
   
    WSACleanup();
   
    return 0;
}

---

First, the code you posted does not compile.

Version "514" in hex is 0x0202 - or version 2.2. Use HIBYTE/LOBYTE to get major/minor numbers.

The "buffer size" is huge because (I think) it specifies the buffer size in bytes, and not items. Really, you should be looping not the buffersize, but buffersize / sizeof(WSAPROTOCOL_INFO) - you're mixing bytes with array indecies.

I just want to thank everyone for their help thus far. Finally, the program works.

I attempted to use HIWORD/LOWORD before.. good call on using the HIBYTE/LOBYTE macros. By themselves, they only yielded little smiley face icons when displayed on dos console, but I casted each value to 'int' and it worked fine. Also, good call on the buffer/sizeof( ).

I think this little exercise illustrates the importance of "hello world" when getting into something new.

Here is the final code.. works as advertised thanks to salem, maxtor, Tonto, and the hugger o' cacti:

Code:

---

#include<iostream>
#include<winsock2.h>

using namespace std;

int main()
{
    WSADATA wsd;
    WSAPROTOCOL_INFO *proto;
    DWORD bufferlength = 0;
   
    if(WSAStartup(MAKEWORD(2,2), &wsd) != 0)
   
      cout << "\n\aWSAStartup failed...";
     
    else   
   
      cout << "\n\nUsing winsock version "
            << (int)HIBYTE(wsd.wVersion) << '.' << (int)LOBYTE(wsd.wVersion);
   
    //This call will fail, but will return the correct buffer size
    WSAEnumProtocols(NULL, NULL, &bufferlength);
   
    cout << "\n\nThere are " << bufferlength/sizeof(WSAPROTOCOL_INFO)
        << " protocols.";
   
    //Allocate the currect buffer size of WSAPROTOCOL_INFO structures
    proto = new WSAPROTOCOL_INFO[bufferlength];
   
    //Populate an array of system protocols
    WSAEnumProtocols(NULL, proto, &bufferlength);
   
    //Step through the array and view some system supported protocol information
    for(int i=0; i<bufferlength/sizeof(WSAPROTOCOL_INFO); i++)
    {
      cout << "\n\n\nProtocol #"  << i+1;
      cout << "\nVersion:        " << proto[i].iVersion;
      cout << "\nAddress Family: " << proto[i].iAddressFamily;
      cout << "\nMax Sockets:    " << proto[i].iMaxSockAddr;
      cout << "\nMin Sockets:    " << proto[i].iMinSockAddr;
      cout << "\nProtocol:      " << proto[i].szProtocol;
    } 
   
    cout << "\n\nPress [ENTER] to continue...";
    cin.get();
   
    WSACleanup();
   
    return 0;
}

---

I read whole thread, It was helpful, Thanx again.