unresolved external symbol ????

[daniloa]

Hi, friends I'm a very begginer on C/C++ development, and I work with telecom development. I has work with another tool, but now I'm going to C++, and I got this error that I don't know how to resolve.
I'm using Microsoft Visual C++ 6/ SP 5 on XP Professional.
When I complile its ok I got no errors, but when I build the program happen this errors messages:

agplay.obj : error LNK2001: unresolved external symbol __imp__dx_stopch
agplay.obj : error LNK2001: unresolved external symbol _ATDV_LASTERR
agplay.obj : error LNK2001: unresolved external symbol _ATDV_ERRMSGP
agplay.obj : error LNK2001: unresolved external symbol __imp__dx_wtring
agplay.obj : error LNK2001: unresolved external symbol __imp__dx_sethook
agplay.obj : error LNK2001: unresolved external symbol __imp__ATDX_FWVER
agplay.obj : error LNK2001: unresolved external symbol __imp__dx_open
agplay.obj : error LNK2001: unresolved external symbol __imp__dx_playf



and the source code is this:



#define _WIN32_WINNT 0x0400

#include <windows.h>

#include <conio.h>
#include <stdio.h>
#include <fcntl.h>

#include <srllib.h>
#include <dxxxlib.h>
#include <sctools.h>

long currentHandle;
long handle;
int event = 0;
int data = 0;
int eventType;
int enableff=0;
int results;

int ch1h;
DV_TPT tpt;
DX_IOTT iott;

DV_DIGIT digp;
void ctrl_c_hdlr(int sig);
DWORD WINAPI play_thread(int *mode);
HANDLE recordh;
int n;
DWORD threadid;
int exitvalue;
int mode;
int fileh;

void ctrl_c_hdlr(int sig){
printf(&quot;Exiting Application\n&quot;
exitvalue=1;
exit(0);
}
char filename[1024];

int modevalue;

int main( int argc, char *argv[])
{

if (argc <= 1) {
printf(&quot;\n Usage: %s \n\n&quot;,argv[0]);
printf(&quot;\n (i.e.) %s data.vox\n&quot;,argv[0]);
exit(1);
}

sprintf(filename,&quot;%s&quot;,argv[1]);

printf(&quot;File to Open: %s\n&quot;,filename);




if ( (ch1h = dx_open(&quot;dxxxB1C1&quot;,0)) == -1){

printf(&quot;ERROR: on dx_open() on device dxxxB1C1\n&quot;
printf(&quot;ERROR: is %d\n&quot;,errno);
exit(0);
}
printf(&quot;Opened dxxxB1C1 (%08lx)\n&quot;, ATDX_FWVER(ch1h));

printf (&quot;Going Onhook . . . . . . . . . . &quot;
if (dx_sethook(ch1h,DX_ONHOOK,EV_SYNC)){
printf (&quot;\n&quot;
printf (&quot;Error setting onhook\n&quot;
exit(0);
}
printf(&quot;done\n&quot;


printf (&quot;Waiting for call . . . . . . . . \n&quot;
if (dx_wtring(ch1h,1,DX_OFFHOOK,30) == -1) {
printf (&quot;\n&quot;
printf(&quot;Error executing dx_wtring\n&quot;
printf(&quot;Last error = %d ErrMsg = %s \n&quot;,ATDV_LASTERR(ch1h),ATDV_ERRMSGP(ch1h));
exit(0);
}
printf (&quot;Ring Event received. Taking Channel Offhook\n&quot;

printf(&quot;\nSelect one of the options and then dial into channel 1\n\n&quot;
printf(&quot;\n*** Press \t'1' \tto play %s at 6Khz ADPCM &quot;,filename);
printf(&quot;\n*** Press \t'2' \tto play %s at 8Khz ADPCM&quot;,filename);
printf(&quot;\n*** Press \t'3' \tto play %s at 6Khz PCM &quot;,filename);
printf(&quot;\n*** Press \t'4' \tto play %s at 8Khz PCM &quot;,filename);

printf(&quot;\n\n*** Press \t's' \tto stop playing&quot;
printf(&quot;\n*** Press \t'ESC' \tto EXIT\n\n\n&quot;

while( 1 ) {

if ( kbhit() ) {
switch( getch() ) {
case 27:
exit(1) ;
case '1':
// record at 6K ADPCM w/ AGC
modevalue=RM_SR6|MD_ADPCM|EV_SYNC;

recordh = CreateThread(NULL,0,play_thread,
&modevalue,
CREATE_SUSPENDED,&threadid);
SetThreadPriority(recordh , THREAD_PRIORITY_NORMAL);
ResumeThread(recordh );
printf(&quot;\n< Hit 's' to stop recording. Hit 'Esc' to exit >\n&quot;
break;
case '2':
// record at 8K ADPCM w/ AGC
modevalue=RM_SR8|MD_ADPCM|EV_SYNC;

recordh = CreateThread(NULL,0,play_thread,
&modevalue,
CREATE_SUSPENDED,&threadid);
SetThreadPriority(recordh, THREAD_PRIORITY_NORMAL);
ResumeThread(recordh);
printf(&quot;\n< Hit 's' to stop recording. Hit 'Esc' to exit >\n&quot;
break;
case '3':
// record at 6K PCM w/ AGC
modevalue=RM_SR6|MD_PCM|EV_SYNC;

recordh = CreateThread(NULL,0,play_thread,
&modevalue,
CREATE_SUSPENDED,&threadid);
SetThreadPriority(recordh, THREAD_PRIORITY_NORMAL);
ResumeThread(recordh);
printf(&quot;\n< Hit 's' to stop recording. Hit 'Esc' to exit >\n&quot;
break;
case '4':
// record at 8K PCM w/ AGC
modevalue=RM_SR8|MD_PCM|EV_SYNC;

recordh = CreateThread(NULL,0,play_thread,
&modevalue,
CREATE_SUSPENDED,&threadid);
SetThreadPriority(recordh, THREAD_PRIORITY_NORMAL);
ResumeThread(recordh);
printf(&quot;\n< Hit 's' to stop recording. Hit 'Esc' to exit >\n&quot;
break;

case 's':
// issuing the stopchannel
if ( dx_stopch(ch1h,EV_SYNC) == -1){
printf(&quot;Error issuing stopchannel\n&quot;
exit(0);
}
printf(&quot;Stop channel issued succesfully\n&quot;

break;
}
}
}

return 0;
}


DWORD WINAPI play_thread(int *mode)
{
static DV_TPT tptx;
static DX_IOTT iottx;

printf(&quot;...play_thread: Inside the thread\n&quot;

switch(*mode){
case(RM_SR6|MD_ADPCM|EV_SYNC):
printf(&quot;...play_thread: Play at RM_SR6|MD_ADPCM|EV_SYNC\n&quot;
break;
case(RM_SR6|MD_PCM|EV_SYNC):
printf(&quot;...play_thread: Play at RM_SR6|MD_PCM|EV_SYNC\n&quot;
break;
case(RM_SR8|MD_PCM|EV_SYNC):
printf(&quot;...play_thread: Play at RM_SR8|MD_PCM|EV_SYNC\n&quot;
break;
case(RM_SR8|MD_ADPCM|EV_SYNC):
printf(&quot;...play_thread: Play at RM_SR8|MD_ADPCM|EV_SYNC\n&quot;
break;

} // end switch


/////////////////////////
printf(&quot;...play_thread: Starting to Play....\n&quot;

tptx.tp_type = IO_EOT;
tptx.tp_termno = DX_MAXDTMF;
tptx.tp_length = 1;
tptx.tp_flags = TF_MAXDTMF;

printf (&quot;...play_thread: Playing on Channel 1. . . . . . . . . . \n&quot;

printf(&quot;...play_thread: About to play file: %s\n&quot;,filename);

if (dx_playf(ch1h,filename,&tptx,*mode) == -1) {
printf (&quot;Error playing %s\n&quot;,ATDV_ERRMSGP(ch1h));
}

printf(&quot;...play_thread: Exiting the play thread\n&quot;
return 1;
}
}

Could you help me ???

Very thanks ...

Danilo Almeida.

 

[mvillara]

Thats mean that at the time of linking the libraries, the functions and definitions:

__imp__dx_stopch
__imp__dx_open
.....
and so on.... can not be found to be linked.

Try to look them and add them to your project.

Good Luck.