The main error would be "not supported" which could happen for e.g.
unix domain sockets, we don't really care, as this is mainly something
for TCP to help out a bit.
This is nice for some callers so they can report an error.
It is also required to support opional address types like
abstract paths for unix domain sockets.
We want to use the protocol id for lookup in the GSocketConnection
code, so we expose it. We also make GSocket store the protocol
as an int for less memory use and to allow platform specific protocols
to be specified.
Also added g_socket_protocol_id_lookup_by_name() to allow the higher
level code to specify the name by string, and g_socket_get_protocol_name()
to get it.
We were sometimes failing in g_socket_check_pending_error because
we were not setting optlen on input and it was sometimes randomly
less than sizeof(int).
This adds:
GInitable - failable object constructor interface
GAsyncInitable - async failable object constructor interface
GSocket - Platform independent lowlevel berkely socket style object
GSocketControlMessage - For passing control messages over GSocket
GUnixFDMessage - unix fd passing socket control message
Some changes were done during the import from gnio to make things
work in glib. For instance, types were moved to other headers, header
file boiler plate were updated to glib style and gio.symbols stuff
was added.
