gcc link shared library against another shared library

[qcp]

Hi all,

I have a shared library A which uses shared library B, and an application P which relies on A.

I don't want to link P against A and B, but to link P against A only, and A against B.

Thanks for your answers

[wje_lf]

This will only make a difference if two functions with the same name exist in both libraries, right?

Here ya go.

#!/bin/bash

cat > a.h <<EOD
void fred(void);
void barney(void);
EOD

cat > b.h <<EOD
void wilma(void);
void barney(void);
EOD

cat > a1.c <<EOD
#include <stdio.h>
#include "b.h"
void fred(void)
{
  printf("this is fred\n");
  wilma();
}
EOD

cat > a2.c <<EOD
#include <stdio.h>
#include "b.h"
void barney(void)
{
  printf("this is barney from library A\n");
}
EOD

cat > b1.c <<EOD
#include <stdio.h>
void wilma(void)
{
  printf("this is wilma\n");
}
EOD

cat > b2.c <<EOD
#include <stdio.h>
void barney(void)
{
  printf("this is barney from library B\n");
}
EOD

cat > main.c <<EOD
#include <stdio.h>
#include "a.h"
int main(void)
{
  fred();
  barney();

  return 0;
}
EOD

gcc -Wall -c a1.c -o a1.o
gcc -Wall -c a2.c -o a2.o
gcc -Wall -c b1.c -o b1.o
gcc -Wall -c b2.c -o b2.o

rm -f a.a b.a

# Arrrre you rrrready, mateys?  (This script is not pirated from elsewhere.)
ar r a.a a1.o
ar r a.a a2.o
ar r b.a b1.o
ar r b.a b2.o

# The following ar optional.

ar -s a.a
ar -s b.a

gcc -Wall main.c a.a b.a -o main

main

The output I get:

this is fred
this is wilma
this is barney from library A

I don't think you can keep library A from linking against itself, but you didn't ask for that. :)

Hope this helps.