pipewire/doc/tutorial2.md

# Tutorial 2

In this tutorial we show how to connect to a PipeWire daemon and 
enumerate the objects that it has.

## Initialization

Let take a look at the following application to start.

```c
#include <pipewire/pipewire.h>

static void registry_event_global(void *data, uint32_t id,
		uint32_t permissions, const char *type, uint32_t version,
		const struct spa_dict *props)
{
	printf("object: id:%u type:%s/%d\n", id, type, version);
}

static const struct pw_registry_events registry_events = {
	PW_VERSION_REGISTRY_EVENTS,
	.global = registry_event_global,
};

int main(int argc, char *argv[])                                                
{                                                                               
        struct pw_main_loop *loop;                                              
        struct pw_context *context;                                             
        struct pw_core *core;                                                   
        struct pw_registry *registry;                                           
        struct spa_hook registry_listener;                                      
                                                                                
        pw_init(&argc, &argv);                                                  
                                                                                
        loop = pw_main_loop_new(NULL /* properties */);                         
        context = pw_context_new(pw_main_loop_get_loop(loop),                   
                        NULL /* properties */,                                  
                        0 /* user_data size */);                                
                                                                                
        core = pw_context_connect(context,                                      
                        NULL /* properties */,                                  
                        0 /* user_data size */);                                
                                                                                
        registry = pw_core_get_registry(core, PW_VERSION_REGISTRY,              
                        0 /* user_data size */);                                
                                                                                
        spa_zero(registry_listener);                                            
        pw_registry_add_listener(registry, &registry_listener,                  
                                       &registry_events, NULL);                 
                                                                                
        pw_main_loop_run(loop);                                                 
                                                                                
        pw_proxy_destroy((struct pw_proxy*)registry);                           
        pw_core_disconnect(core);                                               
        pw_context_destroy(context);                                            
        pw_main_loop_destroy(loop);                                             
                                                                                
        return 0;                                                               
}                                  
```

To compile the simple test application, copy it into a test2.c file and
use:

```
gcc -Wall test2.c -o test2 $(pkg-config --cflags --libs libpipewire-0.3)
```