What 536871023 means..

Using the Celery framework and the librabbitmq package, we start seeing these errors when we specified an invalid host:

Type: 
Value: Error opening socket: Unknown error 536871023

What does the 536871023 means? To understand what the code means, you can fork the librabbitmq code base and look inside the AMQP-related code.

git clone git://github.com/celery/librabbitmq.git

Within the amqp_open_socket(), the error code is returned:

int amqp_open_socket(char const *hostname,                                                                
             int portnumber)   {

.
.
.

    return -amqp_socket_error();   

}

Where amqp_socket_error() is equal to the errno code masked with a constant:

int                                                                                                     
amqp_socket_error(void)                                                                                 
{                                                                                                      
    return errno | ERROR_CATEGORY_OS;                                                                  
}     

This constant is defined in rabbitmq-c/librabbitmq/amqp_private.h:

#define ERROR_CATEGORY_OS (1 << 29) /* OS-specific error codes */  

>>> int(x)
536871023
>>> hex(int(x))
'0x2000006f'

...so we ignore the higher bit and convert the 0x6f..

>>> int(0x6f)
111
>>>

The 111 amounts to a Connection refused error message, which indicates an issue connecting to the RabbitMQ host.