ERROR LNK2019 : UNRESOLVED EXTERNAL ERROR

Question

I am facing LNK2019 error. I have user defined header file - #include "prograamer.h" as shown in the code below. I am trying to make "dll" file for the software.

But when I compile the code i faced this annoying error. Please see the code below :

#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <map>
//#include "..\..\include\programmer.h"
#include "programmer.h"

using namespace std;

--------------
strucutre definition 
--------------
..


// Called once after the network is loaded.
void qpx_NET_postOpen(void)
{
    int exit;
    qps_GUI_printf("Base Plugin opened succesfully. ");
    nLinks = qpg_NET_links();
    nLoops = qpg_NET_detectors();
    qps_GUI_printf("nLinks: %d", nLinks);

    Time = 0;

    for(i = 0; i < n; i++)
    {
        Count[i]          = 0;
        TotalSpeed[i]     = 0.0;
        //Initializing the value for Wo[0]
        Wo[i] = 0.0;
    }

......
...
..

ERROR :-

1>------ Build started: Project: sample 8, Configuration: Debug Win32 ------ 1>dllmain.obj : warning LNK4075: ignoring '/EDITANDCONTINUE' due to '/INCREMENTAL:NO' specification 1> Creating library c:\users\ssaidi\documents\visual studio 2010\Projects\sample 8\Debug\sample 8.lib and object c:\users\ssaidi\documents\visual studio 2010\Projects\sample 8\Debug\sample 8.exp 1>sample 8.obj : error LNK2019: unresolved external symbol _imp_qpg_NET_detectors referenced in function _qpx_NET_postOpen 1>sample 8.obj : error LNK2019: unresolved external symbol _imp_qpg_NET_links referenced in function _qpx_NET_postOpen 1>c:\users\ssaidi\documents\visual studio 2010\Projects\sample 8\Debug\sample 8.dll : fatal error LNK1120: 2 unresolved externals ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

score 0 · Answer 1 · answered Jun 13 '13 at 18:03

0

I'm not familiar with the qpx framework you're using, but your DLL in turn needs to link with the qpx library (static or dynamic). This can be specified in your project property page, under Linker, Input, Additional Dependencies.

answered Jun 13 '13 at 18:03

Scott Jones

2,880
13
19

score 0 · Answer 2 · answered Jun 13 '13 at 18:05

It appears from the error (and from the source code) that you the compiler is able to find the programmer.h file; yet the linker is unable to find the actual implementation of function qpg_NET_links(). Is the source code for that available to the linker?

ERROR LNK2019 : UNRESOLVED EXTERNAL ERROR

2 Answers2