The parameter s is a socket. If it is of
type SOCK_DGRAM, connect() specifies
the peer with which the socket is to be associated. This address is the address
to which datagrams are to be sent if a receiver is not explicitly designated.
This address is the only address from which datagrams are to be received.
If the socket s is of type SOCK_STREAM, connect() attempts to make a connection to
another socket. The other socket is specified by name. name is an address in the communication space of the socket.
Each communication space interprets the name parameter
in its own way. If s is not bound, then s will be bound to an address selected by the underlying transport
provider. Generally, stream sockets can successfully connect()
only once. Datagram sockets can use connect() multiple
times to change their association. Datagram sockets can dissolve
the association by connecting to a null address.
RETURN VALUES
If the connection or binding succeeds, 0 is returned.
Otherwise, -1 is returned and sets errno to indicate the error.
ERRORS
The call fails if:
EACCES
Search permission is denied for a component of the path prefix of the
pathname in name.
EADDRINUSE
The address is already in use.
EADDRNOTAVAIL
The specified address is not available on the remote machine.
EAFNOSUPPORT
Addresses in the specified address family cannot be used with this socket.
EALREADY
The socket is non-blocking, and a previous connection attempt has not yet
been completed.
EBADF
s is not a valid descriptor.
ECONNREFUSED
The attempt to connect was forcefully rejected. The calling program should close(2) the socket
descriptor, and issue another socket(3SOCKET)
call to obtain a new descriptor before attempting another connect() call.
EINPROGRESS
The socket is non-blocking, and the connection cannot be completed immediately.
You can use select(3C)
to complete the connection by selecting the socket for writing.
EINTR
The
connection attempt was interrupted before any data arrived by the delivery
of a signal. The connection, however, will be established asynchronously.
EINVAL
namelen is not the size of a valid address for the specified
address family.
EIO
An I/O
error occurred while reading from or writing to the file system.
EISCONN
The socket is already connected.
ELOOP
Too
many symbolic links were encountered in translating the pathname in name.
ENETUNREACH
The network is not reachable from this host.
EHOSTUNREACH
The remote host is not reachable from this host.
ENOENT
A
component of the path prefix of the pathname in name
does not exist.
ENOENT
The
socket referred to by the pathname in name does
not exist.
ENOSR
There
were insufficient STREAMS resources
available to complete the operation.
ENXIO
The
server exited before the connection was complete.
ETIMEDOUT
Connection establishment timed out without establishing a connection.
EWOULDBLOCK
The socket is marked as non-blocking, and the requested operation would block.
The following errors are specific to connecting names
in the UNIX domain. These errors might not apply in future versions of the
UNIX IPC domain.
ENOTDIR
A component of the path prefix of the pathname in name is not a directory.
ENOTSOCK
s is not a socket.
ENOTSOCK
name is not a socket.
EPROTOTYPE
The file that is referred to by name is a socket
of a type other than type s. For example, s is a SOCK_DGRAM
socket, while name refers to a SOCK_STREAM socket.
ATTRIBUTES
See attributes(5)
for descriptions of the following attributes:
