Query related to Hiding symbol in Shared Library

noble_curious · 01-01-2009, 04:18 AM

Hi,

I have a question:

Suppose i have a source code file as

test.c
------------

Code:

...
...
...
#include <stdio.h>
void __attribute__ (( visibility ("hidden") )) sayHello (void)
{
   printf("hello");
}
....

i compile this file and make shared library using gcc say named as libhello.so

now although the function sayHello is not exported to the libhello.so
but when i run this command:

Code:

shell> nm libhello.so

the resultant display shows one of the symbol there as sayHello

Is this possible that I completely hide this symbol so that nm doesnt read this local function in the library.

Kind Regards

wje_lq · 01-01-2009, 04:53 AM

There are two ways to do this.

One way is to use program strip. Do this at the command line:

Code:

man strip

Another way is to do it at compile time by declaring the function as static. But you probably knew this.

noble_curious · 01-01-2009, 05:07 AM

@wje_lq

Thank you sir. You really solved my issue. I really had noknowledge about the 'strip' utility. It is really wonderfull. I removed all the unnecessary symbols and there is no effect on my application.

Thankyou again and Kind Regards