error which call from main.c to viewcontroller.m as button - ios6

Question

this is my main.c
static int l_psd_stop_f(void)
{
int res;
int fd_psd_socket;
if(pthread_mutex_lock(&l_mutex_wrc)) {
LOG_ERR("Can not lock WRC mutex");
return -1;
}
fd_psd_socket = l_s_wrc.fd_psd;
l_s_wrc.fd_psd = -1;
if(pthread_mutex_unlock(&l_mutex_wrc)) {
LOG_ERR("Can not unlock WRC mutex");
return -1;}
res = l_stop_psd_receiver_f(fd_psd_socket);
fd_psd_socket = -1;
if(res < 0) {
LOG_ERR("Can not close PSD socket %d : %s", res, strerror(errno));
return -1;
}
return 0;
}
i want to call and refer to this codes but it bring me error when i click on the button which run on x-code ipad simulator.
this is on ViewController.m
- (IBAction)disconnect:(id)sender {
[self l_psd_stop_f];}

Answer 1

instead of declaring "l_psd_stop_f" in your main.c, put it in your ViewController.m and declare it like this:
- (int) l_psd_stop_f
{
int res;
int fd_psd_socket;
...
...
...
}
And then your "disconnect" action will compile and should work.
By declaring it as "static int l_psd_stop_f(void)" in your main.c, it was a C function that was probably only available to any function calling it from within main.c. But that function wasn't available to your view controller.
So what I'm having you do is change that C function into an Objective-C method, a member of that ViewController class.