Question

I have a small query as below.

I have created a shared library from below code.

help.h

#include<iostream>
#include<signal.h>
#include<unistd.h>

using namespace std;

void killMe(int sig_num);

void printMe(void);

help.cpp

#include<iostream>
#include<signal.h>
#include<unistd.h>

using namespace std;

void killMe(int sig_num)
{
    cout<<"Timeout occurred."<<endl;
    raise(SIGKILL);
}

void printMe()
{
    cout<<"This is help.cpp"<<endl;
}

[root@localhost DL]# nm -n /usr/local/lib/libmyhelp.so | grep " T "
00000584 T _init
00000760 T _Z6killMei
000007ae T _Z7printMev
00000864 T _fini
[root@localhost DL]#

Checking the output of nm, i see that killMe and printMe functions’ names have been changed a little. Is there any way to retain the same name in shared library as it is in cpp code? Thanks.

Answer 1

This is due to C++ name mangling. To turn it off, declare the functions as extern "C".

help.h:

#include<iostream>
#include<signal.h>
#include<unistd.h>

using namespace std;

extern "C" {

void killMe(int sig_num);

void printMe(void);

}