QLocalSocket should support the abstract namespace on Linux

man 7 UNIX:

• abstract: an abstract socket address is distinguished by the fact
  that sun_path[0] is a null byte ('\0'). All of the remaining bytes
  in sun_path define the "name" of the socket. (Null bytes in the
  name have no special significance.) The name has no connection with
  file system pathnames. The socket's address in this namespace is
  given by the rest of the bytes in sun_path. When the address of an
  abstract socket is returned by getsockname(2), getpeername(2), and
  accept(2), its length is sizeof(struct sockaddr_un), and sun_path
  contains the abstract name. The abstract socket namespace is a non‐
  portable Linux extension.

Note: The abstract socket namespace is a non‐portable Linux extension.

In some secured Linux systems (chrooted environment, cgroup, nfs and so on ) there is no writable places at all. So some Qt programs does not work.

I think, especially for linux, "abstract" sockets should be created instead of generic. Most of the modern programs for linux (DBus, Xorg, udev and many more).

P.S. Please convert to suggestion for future release instead of closing bug as "invalid".