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undefined reference to....

Hi! i am trying to compile/link a simple application that uses a library called OpenDBX. I have already compiled and installed that library. Now, i am trying to do a simple client of it.

The client (Prueba.c) is just like this:

Code:

#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>

#include <odbx.h>



int main(void) {

        puts("Hello World!!");

        

                int err;

                odbx_t* handle;

        

                if( ( err = odbx_init( &handle, "mysql", "127.0.0.1", "" ) ) < 0 )

                {

                    fprintf( stderr, "odbx_init(): %s\n", odbx_error( handle, err ) );

                    return err;

                }

                

                return EXIT_SUCCESS;

}

When i try to compile that program (Prueba.c), i has this error:

cc -c -o Prueba.o Prueba.c
gcc -O2 -g -Wall -fmessage-length=0 -L/usr/local/lib -L/usr/local/lib/opendbx -L/usr/local/lib/pkgconfig -o Pruebas Prueba.o
Prueba.o: In function `main':
Prueba.c:(.text+0x3c): undefined reference to `odbx_init'
Prueba.c:(.text+0x57): undefined reference to `odbx_error'
collect2: ld returned 1 exit status
make: *** [Pruebas] Error 1

Those functions (odbx_error and odbx_init are both defined in odbx.h (the header of openDBX y need to include).

I have checked that openDBX libraries are okey. There are in /usr/local/lib , /usr/local/lib/opendbx and /usr/local/lib/pkgconfig.

My makefile is like this:

Code:

COMPILER = gcc



CCFLAGS =        -O2 -g -Wall -fmessage-length=0 



OBJS =                Prueba.o



LIBS = 



TARGET =        Pruebas



LDFLAGS = -L/usr/local/lib -L/usr/local/lib/opendbx -L/usr/local/lib/pkgconfig



$(TARGET):        $(OBJS)

        ${COMPILER} ${CCFLAGS} $(LDFLAGS) -o $(TARGET) $(OBJS) $(LIBS)



all:        $(TARGET)



clean:

        rm -f $(OBJS) $(TARGET)

So...can someone please tell what does this error mean ? i think that it doesn't found the library asosiated with de odbx.h, but i am not sure.

Very thanks

Mariano

Quote:

Originally Posted by crapodino (Post 3021414)

Hi! i am trying to compile/link a simple application that uses a library called OpenDBX. I have already compiled and installed that library. Now, i am trying to do a simple client of it.

So I presume you never found the solution to your other problem?

Quote:

Originally Posted by crapodino (Post 3021414)

The client (Prueba.c) is just like this:
[CODE]So...can someone please tell what does this error mean ? i think that it doesn't found the library asosiated with de odbx.h, but i am not sure.

Yes, that’s exactly what it means—you don’t have any libraries specified (though you do have a library search path).

Here’s how I would modify your Makefile:

Code:

COMPILER = gcc



ODBX_CFLAGS := $(shell pkg-config --cflags opendbx)

ODBX_LIBS  := $(shell pkg-config --libs  opendbx)



CCFLAGS =        -O2 -g -Wall -fmessage-length=0 $(ODBX_CFLAGS)



OBJS =                Prueba.o



LIBS =                $(ODBX_LIBS)



TARGET =        Pruebas



LDFLAGS = -L/usr/local/lib -L/usr/local/lib/opendbx -L/usr/local/lib/pkgconfig



$(TARGET):        $(OBJS)

        ${COMPILER} ${CCFLAGS} $(LDFLAGS) -o $(TARGET) $(OBJS) $(LIBS)



all:        $(TARGET)



clean:

        rm -f $(OBJS) $(TARGET)