connect(2)connect(2)Nameconnect - initiate a connection on a socket
Syntax
#include <sys/types.h>
#include <sys/socket.h>
connect(s, name, namelen)
int s;
struct sockaddr *name;
int namelen;
Description
The call initiates a connection on a socket. The parameter s is a
socket. If the socket is of type SOCK_DGRAM, this call permanently
specifies the peer to which datagrams are sent. If it is of type
SOCK_STREAM, this call attempts to make a connection to another socket.
The other socket is specified by name, which is an address in the com‐
munications space of the socket. Each communications space interprets
the name parameter in its own way. The size of the structure sockaddr
is namelen.
Return Values
If the connection or binding succeeds, then 0 is returned. Otherwise,
a -1 is returned, and a more specific error code is stored in errno.
Diagnostics
The call fails under the following conditions:
[EBADF] The s is not a valid descriptor.
[ENOTSOCK] The s is a descriptor for a file, not a socket.
[EADDRNOTAVAIL]
The specified address is not available on this machine.
[EAFNOSUPPORT] Addresses in the specified address family cannot be used
with this socket.
[EINPROGRESS] The connection is requested on a socket with FNDELAY set
(using
[EISCONN] The socket is already connected.
[ETIMEDOUT] Connection establishment timed out without establishing
a connection.
[ECONNREFUSED] The attempt to connect was forcefully rejected.
[ENETUNREACH] The network is not reachable from this host.
[EADDRINUSE] The address is already in use.
[EFAULT] The name parameter specifies an area outside the process
address space.
[EWOULDBLOCK] The socket is nonblocking, and the connection cannot be
completed immediately. You can select the socket for
writing by using the system call while it is connecting.
The following errors are specific to connecting names in the ULTRIX
domain:
[ENOTDIR] A component of the path prefix is not a directory.
[ENAMETOOLONG] A component of a pathname exceeded 255 characters, or an
entire path name exceeded 1023 characters.
[ENOENT] The named socket does not exist.
[EACCES] Search permission is denied for a component of the path
prefix.
[ELOOP] Too many symbolic links were encountered in translating
the pathname.
See Alsoaccept(2), fcntl(2), getsockname(2), select(2), shutdown(2), socket(2)connect(2)