LwIP issue: "undefined reference".

Hi, I'm working on a project for school that will be using lwIP, and I need to familiarize myself with how it works. For now I'm just trying to write a simple test program. It doesn't even do anything yet, but I cannot for the life of me get it to compile:

Code:

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#include "lwip\udp.h"

void udp_packet_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port);

main(){
        // Create a new pcb.
        struct udp_pcb * pcb;
        pcb = udp_new();
        if (pcb == NULL)
                return -1;

        // Bind to any IP on port 60,000.
        if (udp_bind(pcb, IP_ADDR_ANY, 60000) != ERR_OK)
                return -2;

        // On datagram receipt, call udp_packet_recv.
        udp_recv(pcb, udp_packet_recv, NULL);
}

void udp_packet_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port){
        if (p != NULL){
                // TODO: Case handling GET packet.
                // TODO: Case handling data receipt.
       
                pbuf_free(p); // Free pbuf when finished.
        }
}

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Every time I try to compile this, I get the following errors:

Code:

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C:\Users\ZACHAR~1\AppData\Local\Temp\cc1kZ7BP.o:client.c:(.text+0xf): undefined reference to `udp_new()'

C:\Users\ZACHAR~1\AppData\Local\Temp\cc1kZ7BP.o:client.c:(.text+0x3d): undefined reference to `udp_bind(udp_pcb*, ip_addr*, unsigned short)'

C:\Users\ZACHAR~1\AppData\Local\Temp\cc1kZ7BP.o:client.c:(.text+0x5d): undefined reference to `udp_packet_recv(void*, udp_pcb*, pbuf*, ip_addr*, unsigned short)'

C:\Users\ZACHAR~1\AppData\Local\Temp\cc1kZ7BP.o:client.c:(.text+0x69): undefined reference to `udp_recv(udp_pcb*, void (*)(void*, udp_pcb*, pbuf*, ip_addr*, unsigned short), void*)'

C:\Users\ZACHAR~1\AppData\Local\Temp\cc1kZ7BP.o:client.c:(.text+0x8e): undefined reference to `pbuf_free(pbuf*)'

collect2: ld returned 1 exit status

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I read something online about linking "lwip4", but have not been able to find anything about that file elsewhere. (I can't even figure out where I originally read that...) I believe I've included all the requisite files!
http://i20.photobucket.com/albums/b2...hots/files.png
I'm using "lwip-win32-msvc-0.1", which is based on the CVS version of lwIP from 23-01-2002. It is available for download here: lwip-win32-msvc-0.1.zip - Ãâ·Ñ¸ßËÙÏÂÔØ - ¹²Ïí×ÊÁÏ

The computer I am attempting to compile on is a Sony VPCF126FM, with no hardware modifications of any kind: http://www.docs.sony.com/release/spe...26FMB_mksp.pdf

I'm using MiniGW command line " g++ client.c -o client.exe" to compile. (Nothing fancy.)
Can anybody help me out here? This has become a real sticking point.

That command line is conspicuously missing -l<name of library goes here>.

I managed to find "lwip4.dsp" and "lwip4.dsw" in the "lwip-win32-msvc-0.1\proj\msvc6" directory. I'm not sure these are the right files though, and attempting to link them with the following commands has not worked.

Code:

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-llwip4.dsp
-llwip4.dsw

-l lwip4.dsp
-l lwip4.dsw

-llwip4
-l lwip4

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I keep getting some variation of "ld.exe: cannot find -llwip4".

.dsp and .dsw aren't libraries. They are, if I recall correctly, Visual Studio's internal project file format from version 6 or something. Your libraries will end in .lib or .dll (or possibly .a or .so).

Yeah, I kinda figured that from the parts of the .dsp file I was able to read.. but I can't find any other files by the name of "lwip4", either in the package I'm using or on the internet.

Anybody have any ideas as to where I might find a library that fits the bill?

Quote:

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Originally Posted by DaMunky89

Yeah, I kinda figured that from the parts of the .dsp file I was able to read.. but I can't find any other files by the name of "lwip4", either in the package I'm using or on the internet.

Anybody have any ideas as to where I might find a library that fits the bill?

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If the package you're using doesn't have any .lib or .dll files at all, then you either downloaded source-code-only (which makes it your responsibility to make the library and/or put the code in your own project) or you got a bad download.

There is also no reason in the world that your library has to be called lwip4.lib or lwip4.dll.

Yeah.. I found people talking on that Chinese site about lwip-win32-msvc-0.1, somehow using the .dsp and .dsw file to compile the .lib using Visual Basic 6? So it seems like this download is source-only. Next I'm going to try and figure compiling the lib myself I guess.