#include <nng/nng.h>
enum sockaddr_family {
NNG_AF_ABSTRACT = 6,
};
typedef struct {
uint16_t sa_family;
uint16_t sa_len;
char sa_name[107];
} nng_sockaddr_abstract;nng_sockaddr_abstract(5)
NAME
nng_sockaddr_abstract - abstract IPC socket address
SYNOPSIS
DESCRIPTION
An nng_sockaddr_abstract is the flavor of nng_sockaddr
used to represent addresses associated with IPC communication using “abstract” sockets.
Abstract sockets are only supported on Linux at present. These sockets have a name that is simply an array of bytes, with no special meaning. Abstract sockets also have no presence in the file system, do not honor any permissions, and are automatically cleaned up by the operating system when no longer in use.
| Support for abstract sockets is a new feature in NNG, and it is only available on Linux. As such their use is not recommended for portable applications. |
The following structure members are present:
sa_family-
This field will always have the value
NNG_AF_ABSTRACT. sa_len-
This field provides the name of the length stored in
sa_name. sa_name-
This field holds the name of the abstract socket. The bytes of name can have any value, including zero.
The name does not include the leading NUL byte used on Linux to discriminate between
abstract and path name sockets.
|
Auto Bind
An empty value (sa_len equal to zero) can be used on listening sockets to request the
system allocate a name.
On Linux systems, this will result in a name with either 5 or 8 hexadecimal ASCII characters.
The name chosen can be obtained by retrieving the NNG_OPT_LOCADDR option on the listening entity.
| Because a zero length name is used to indicate auto bind be used, it is impossible to specify an actual empty name. This name are not supported by NNG, although the underlying system can support it. The use of that name is inadvisable anyway. |