Question

I try to compile a program I have to control a DAQ device. In Windows, g++ compile and links OK, but in Linux it doesn’t. The linker (called by G++) displays:

g++ -Wall -o "acelerar-30-0" "acelerar-30-0.cpp" (en el directorio: /home/poly/)
/tmp/ccRLpB4q.o: In function `main':
acelerar-30-0.cpp:(.text+0x429): undefined reference to `AdxInstantAoCtrlCreate'
collect2: ld returned 1 exit status
Ha fallado la compilación.

The cpp file is this (cut):

include stdlib.h
include stdio.h
include math.h
include "compatibility.h"
include "bdaqctrl.h"
include "comunes.h"
using namespace Automation::BDaq;
define deviceDescription L"USB-4704,BID#0"
int32       channelStart = 0;
int32       channelCount = 1;
double      voltaje[0];
int32       modo;
int32       ms;
int main(int argc, char* argv[])
{
    if (argc!=3)
        salidaerror(argv[0],1);
    channelStart = atoi(argv[1]);
    ms = atoi(argv[2]);
    if (channelStart<0||channelStart>1||ms<10)
        salidaerror(argv[0],1);
    ErrorCode ret = Success;
    InstantAoCtrl * instantAoCtrl = AdxInstantAoCtrlCreate();
...

I have been several hours on this, and can’t find the answer. The SDK is for Debian/Ubuntu, and it has the same code for Linux and Windows.

Any hints? Thanks

EDIT: Removed some marks as the formatting was incorrect

Answer 1

In my (limited) experience, typical gcc behavior will require that you specify the library containing that function as an argument on the command line like so:

-lsome_library

This is required even if the library is in your library path (additional library paths can be specified with -L). Find the appropriate library file containing that function and use its filename minus extensions and leading “lib” in the argument format above.