Thread: Question about libpq++

I've installed pgsql 6.4.2
It includes libpq++
I've tried to play with it...
Simply
#include <stdlib.h>
#include <libpq++.h>
int main(void)
{
      PgEnv a;
      a.SetEnv(NULL,NULL,NULL,NULL,NULL);
      return 0;
}

during compilation with "g++ -o pgsetenv pgsetenv.cpp
-I/usr/local/pgsql/include" I've got an error message:
/var/tmp/ccxg22111.o: Undefined symbol `___5PgEnv' referenced from text segment
....

What to do?

thanks,
       Q

Alexey,

It appears you've forgotten to link in the libpq++ library with a -l on
the command line.  You may also need a -L to tell the compiler where to
find the library.

    Randy Barrett

On Wed, 27 Jan 1999, Alexey V. Meledin wrote:

> I've installed pgsql 6.4.2
> It includes libpq++
> I've tried to play with it...
> Simply
> #include <stdlib.h>
> #include <libpq++.h>
> int main(void)
> {
>       PgEnv a;
>       a.SetEnv(NULL,NULL,NULL,NULL,NULL);
>       return 0;
> }
>
> during compilation with "g++ -o pgsetenv pgsetenv.cpp
> -I/usr/local/pgsql/include" I've got an error message:
> /var/tmp/ccxg22111.o: Undefined symbol `___5PgEnv' referenced from text segment
> ....
>
> What to do?
>
> thanks,
>        Q
>
>
>
>

"Alexey V. Meledin" wrote:
>
> I've installed pgsql 6.4.2
> It includes libpq++
> I've tried to play with it...
> Simply
> #include <stdlib.h>
> #include <libpq++.h>
> int main(void)
> {
>       PgEnv a;
>       a.SetEnv(NULL,NULL,NULL,NULL,NULL);
>       return 0;
> }
>
> during compilation with "g++ -o pgsetenv pgsetenv.cpp
> -I/usr/local/pgsql/include" I've got an error message:
> /var/tmp/ccxg22111.o: Undefined symbol `___5PgEnv' referenced from text segment
> ....
>
> What to do?
>
> thanks,
>        Q
Sound's like a link problem to me. The linker say's that he
can not find theses symbol.

Perhaps you add the options "-L/usr/local/pgsql/lib -lpg -lpg++" to
your linker options.

Hope that helps.

    Ralf

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