This function should be called by the eCos application at startup. It performs the initialization of the lwIP network stack and any configured network device drivers.
If either of the IPv4
CYGSEM_LWIP_DHCP_WAIT_DHCP_COMPLETE or IPv6 stateless
options are enabled then this initialization routine will wait for up to the
maximum of the configured timeouts for the network interfaces to acquire the
relevant addresses. If the network services are slow in providing a required
address then it is possible that this function will exit with the interface not
yet reachable from the network, so applications should always validate
interfaces after calling this initialization routine. The wait support is
provided by this routine to ensure a common implementation. If required the
function can be called again to re-wait for the configured timeouts, but it
should be noted that subsequent calls do not re-initialize
the lwIP stack.
The value 0 is returned on completion of the initialization. The value 1 is returned if the routine has previously been called, and is not an indication of a failure to initialise.